What is computer?
The computer is an electronic device that is used to solve various problems according to a set of instruction given to it. The word computer is derived from a word compute, with means, to Calculate.
More …..
In 1640 a fransy man create a 8digits Machine this is only ( + and - ) this proper introduce in 1942.
A girl Agctakng first time introduced programming language in 1933 and the word to see are work in
1944 and this girl design a Automatic computer in 1934
Next introduced a Punching Holes his name is (Tabulator)
Computer name use in first and final in 1971……………. In 1971 Intel computer First Personal computer ins introduced in 1974 this seas (Micro instrumentation Telemetry) name (ALATAIR 880) System this with out Keyboard and Mouse.
A computer has four Functions:
Some Beginning Terms:
Hardware: The Physical parts of the computer are called
Computer Hardware: These are the things that can be seen and touched
Example the CPU. Monitor. Drivers. Mouse. Keyboard. Etc
Software: A set of computer instruction given to the computer to solve a problem is called software.
Default:
The original setting is called default for example Ms word when open you see the size of text is 12. Then you told this is original setting mean default.
Computer Characteristics
Speed: Computer works at a very high sped and are much faster than humans. A second is very large time period for computer. A computer can perform billions of calculation in a second. The time used by a computer to perform an operation is called processing speed. Computer speed is measured in Mega Hertz (MHz)
Reliability:
Failures are usually due to human error, one way or another.
A man to a calculation in billions digits may be suffer with some problem and mind error but computer is reliable machine.
Storage:
A computer can keep huge amounts of data.
Accuracy:
Accuracy means to provide results without any errors.
Recalling:
A computer can recall the stored data and information as and when required. The data stored in the computer can be used at a later.
The computer can recall the required data in a few seconds.
Classification of digital computer:
Computer is classified according to size, speed and memory capacity.
Computer is of different types.
Main frame computer
Mini computers
Micro computers
Super computers
Laptop
Programs:
Programs are the sets of instructions that direct the computer.
Commands:
Commands are special codes or key words that the user inputs to perform a task.
Out put
The information of computer is called out put
Printer
Monitor
Speaker
Operating system
Operating system
Single-user Operating systems
A type of operating system in which only user can work at time is called single-user operating system. Dos. Windows 8x are example of single- user operating system. Dos work on command it is most sing-user operating system. Dos works on command it is most compatible with hardware
Multi- operating systems / (multi tasking operating systems)
A type of operating system in which more than one user can work at a time is called Multi- tasking operating system. Unix, Linux,
Windows NT/ 2000 are examples of single- user operating systems.
Application software: / utility software
Application software is drivers and any other software mean Ms word and win boost, flash free hand. Drivers to hand. Drivers to handover in the hardware mean looking but application software is different work this to operating system . this under it to the operating system
+
Application software is the software that is used to perform tasks such as word- processing, a spreadsheet or database etc. it is importance to realize that the application software uses the operating system in order to function. You can think of the operating system as the ‘base’ software, with the application software running of top of the operating system software.
Types of RAM
There are two types of Ram
• Static RAM
• Dynamic (DRAM)
Static RAM
Static RAM is more expensive. It required more amount of space for a given amount of data that dynamic RAM. It does not need to be power-refreshed and is therefore faster to access.
Dynamic RAM;
DRAM is the least expensive kind of RAM. Dynamic RAM uses a kind of capacitor that should be recharged again and again. A power refresh is required after each read. DRAM must be refreshed many times in a second. That is why it is slow.
ROM (READ ONLY MEMORY)
Read only memory as the name suggests is a special type of memory chip that hold software that can be read but only written to. A good example is the ROM- BIOS chip, which contain read only software. Often network cards and video cards also contain ROM chip.
CD-ROM:-
CD –ROM stands for compact disk read only memory. The data on a CD-ROM can only be read and cannot be removed or changes. It is most commonly used type of optical disk. It has the storage capacity of up to 650 MB. It is used for storing large amounts of data and application programs.
DVD-ROM:-
DVD-ROM stands for Digital Video Disk Read Only Memory. A DVD operates similar to a CD-ROM disk. A DVD uses a laser with shorter wavelength. A laser with shorter wavelength can read smaller holes on a optical disk. Small size holes on the disk surface increases its data storage capacity. A DVD can store data up to 10 GB of data. Its storage capacity is seven times more than that of the CD-ROM.
What is processing?
1 bit = one on or off position
1 byte = 8 bits
So 1 byte can be one of 256 possible combinations of 0 and 1.
Numbers written with just 0 and 1, are called binary numbers.
Control unit
This is the part of the computer that controls the machine Cycle. It is takes numerous cycles to do even a simple addition of two numbers.
Fetch – get an instruction from main memory
Decode – translate it into computer commands
Execute- actually process the command
Store- writes the result to main memory
ALU
Stand for Arithmetic logic unit
This is the part executes the computer’s commands.
A command must be either a basic arithmetic operation +-*/ or one of the logical comparisons.
Computer communication
Computer communication is the transmission of data information over a communications channel between two computers.
Communication between computers can be as simple as cabling two computers to the same printers. It can be as complex as a computer at NASA sending messages through an elaborate system of relays and satellites to tell a computer on Mars how to drive around without hitting the rocks.
Depending on the context, for computer communications you might use the terms:
Data communication for transmission of data and information over a communications channel
Telecommunication for any long- distance communication, especially television
Communications channel :
A communications channel , also called a communications line or link, is the path that the data follows as it is transmitted from one computer to another .
Transmission Media
Transmission media just means the physical materials that are used to transmit data between computers.
Cables :
Twisted wire : (Phone line)
Coaxial cable: (round insulated wire ) house cable
Fiber optic line ( glass fiber ) smaller cable Faster (speed of light)
Signals
Tow types of signals are used for data transmission
Digital and analog
digital
A Digital signal is a stream of 0’s and 1’s .
An analog signal :
It is particularly useful for wave data like sound waves .Analog signals are what your normal phone line and sound speakers use.
Modems
Communications between computers use the telephone system for at least part of the channel Such a device is the modem , which comes from Modulate / Demodulate , Which is what a modem s dose . It modulates a digital signal from the computer into an analog one to send data out over the phone line. Than for an incoming signal tit demodulates the analog signal into a digital one.
Downloading means to transfer a transfer a file to your computer
Uploading means to transfer a file to your computer to another .
Networks types
LAN , MAN
LAN: Local Area Network LANs would be within the same office, a single building , or several building s close as a LAN .
WAN Wide Area Network Which would be all networks too large to be LANs .WAN would be most useful for large companies like Microsoft, IBM etc.
Star Network
The stare pattern connects everything to one host, Gives close control of data . Each PC seen all the data . If a compute other than the host fails , no other computer is down.
BUS
The bus pattern connects the computer to the same communications line
Ring
The ring pattern connects the computers and other devices one to the other in a circle . There is no central host computer that holds all the dat
"Computer technology" redirects here. For the company, see Computer Technology Limited.
Computer
A computer is a programmable machine designed to automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem. An important class of computer operations on some computing platforms is the accepting of input from human operators and the output of results formatted for human consumption. The interface between the computer and the human operator is known as the user interface.
Conventionally a computer consists of some form of memory, at least one element that carries out arithmetic and logic operations, and a sequencing and control unit that can change the order of operations based on the information that is stored. Peripheral devices allow information to be entered from an external source, and allow the results of operations to be sent out.
A computer's processing unit executes series of instructions that make it read, manipulate and then store data. Conditional instructions change the sequence of instructions as a function of the current state of the machine or its environment.
The first electronic digital computers were developed in the mid-20th century (1940–1945). Originally, they were the size of a large room, consuming as much power as several hundred modern personal computers (PCs).[1] In this era mechanical analog computers were used for military applications.
First general-purpose computers
In 1801, Joseph Marie Jacquard made an improvement to the textile loom by introducing a series of punched paper cards as a template which allowed his loom to weave intricate patterns automatically. The resulting Jacquard loom was an important step in the development of computers because the use of punched cards to define woven patterns can be viewed as an early, albeit limited, form of programmability.
It was the fusion of automatic calculation with programmability that produced the first recognizable computers. In 1837, Charles Babbage was the first to conceptualize and design a fully programmable mechanical computer, his analytical engine.[20] Limited finances and Babbage's inability to resist tinkering with the design meant that the device was never completed ; nevertheless his son, Henry Babbage, completed a simplified version of the analytical engine's computing unit (the mill) in 1888. He gave a successful demonstration of its use in computing tables in 1906. This machine was given to the Science museum in South Kensington in 1910.
A succession of steadily more powerful and flexible computing devices were constructed in the 1930s and 1940s, gradually adding the key features that are seen in modern computers. The use of digital electronics (largely invented by Claude Shannon in 1937) and more flexible programmability were vitally important steps, but defining one point along this road as "the first digital electronic computer" is difficult.Shannon 1940 Notable achievements include.
Computers using vacuum tubes as their electronic elements were in use throughout the 1950s, but by the 1960s had been largely replaced by semiconductor transistor-based machines, which were smaller, faster, cheaper to produce, required less power, and were more reliable. The first transistorised computer was demonstrated at the University of Manchester in 1953.[31] In the 1970s, integrated circuit technology and the subsequent creation of microprocessors, such as the Intel 4004, further decreased size and cost and further increased speed and reliability of computers. By the late 1970s, many products such as video recorders contained dedicated computers called microcontrollers, and they started to appear as a replacement to mechanical controls in domestic appliances such as washing machines. The 1980s witnessed home computers and the now ubiquitous personal computer. With the evolution of the Internet, personal computers are becoming as common as the television and the telephone in the household
Bugs
Main article: software bug
The actual first computer bug, a moth found trapped on a relay of the Harvard Mark II computer
Errors in computer programs are called "bugs". They may be benign and not affect the usefulness of the program, or have only subtle effects. But in some cases they may cause the program or the entire system to "hang" – become unresponsive to input such as mouse clicks or keystrokes – to completely fail, or to crash. Otherwise benign bugs may sometimes be harnessed for malicious intent by an unscrupulous user writing an exploit, code designed to take advantage of a bug and disrupt a computer's proper execution. Bugs are usually not the fault of the computer. Since computers merely execute the instructions they are given, bugs are nearly always the result of programmer error or an oversight made in the program's design.[33]
Rear Admiral Grace Hopper is credited for having first used the term "bugs" in computing after a dead moth was found shorting a relay in the Harvard Mark II computer in September 1947.[3
Machine code
In most computers, individual instructions are stored as machine code with each instruction being given a unique number (its operation code or opcode for short). The command to add two numbers together would have one opcode, the command to multiply them would have a different opcode and so on. The simplest computers are able to perform any of a handful of different instructions; the more complex computers have several hundred to choose from, each with a unique numerical code. Since the computer's memory is able to store numbers, it can also store the instruction codes. This leads to the important fact that entire programs (which are just lists of these instructions) can be represented as lists of numbers and can themselves be manipulated inside the computer in the same way as numeric data. The fundamental concept of storing programs in the computer's memory alongside the data they operate on is the crux of the von Neumann, or stored program, architecture. In some cases, a computer might store some or all of its program in memory that is kept separate from the data it operates on. This is called the Harvard architecture after the Harvard Mark I computer. Modern von Neumann computers display some traits of the Harvard architecture in their designs, such as in CPU caches
While it is possible to write computer programs as long lists of numbers (machine language) and while this technique was used with many early computers,[35] it is extremely tedious and potentially error-prone to do so in practice, especially for complicated programs. Instead, each basic instruction can be given a short name that is indicative of its function and easy to remember – a mnemonic such as ADD, SUB, MULT or JUMP. These mnemonics are collectively known as a computer's assembly language. Converting programs written in assembly language into something the computer can actually understand (machine language) is usually done by a computer program called an assembler.
Programming language
Main article: Programming language
Programming languages provide various ways of specifying programs for computers to run. Unlike natural languages, programming languages are designed to permit no ambiguity and to be concise. They are purely written languages and are often difficult to read aloud. They are generally either translated into machine code by a compiler or an assembler before being run, or translated directly at run time by an interpreter. Sometimes programs are executed by a hybrid method of the two techniques.
Program design
Program design of small programs is relatively simple and involves the analysis of the problem, collection of inputs, using the programming constructs within languages, devising or using established procedures and algorithms, providing data for output devices and solutions to the problem as applicable. As problems become larger and more complex, features such as subprograms, modules, formal documentation, and new paradigms such as object-oriented programming are encountered. Large programs involving thousands of line of code and more require formal software methodologies. The task of developing large software systems presents a significant intellectual challenge. Producing software with an acceptably high reliability within a predictable schedule and budget has historically been difficult; the academic and professional discipline of software engineering concentrates specifically on this challenge.
Components
Main articles: Central processing unit and Microprocessor
A general purpose computer has four main components: the arithmetic logic unit (ALU), the control unit, the memory, and the input and output devices (collectively termed I/O). These parts are interconnected by busses, often made of groups of wires.
Inside each of these parts are thousands to trillions of small electrical circuits which can be turned off or on by means of an electronic switch. Each circuit represents a bit (binary digit) of information so that when the circuit is on it represents a "1", and when off it represents a "0" (in positive logic representation). The circuits are arranged in logic gates so that one or more of the circuits may control the state of one or more of the other circuits.
The control unit, ALU, registers, and basic I/O (and often other hardware closely linked with these) are collectively known as a central processing unit (CPU). Early CPUs were composed of many separate components but since the mid-1970s CPUs have typically been constructed on a single integrated circuit called a microprocessor.
Control unit
Main articles: CPU design and Control unit
Diagram showing how a particular MIPS architecture instruction would be decoded by the control system.
The control unit (often called a control system or central controller) manages the computer's various components; it reads and interprets (decodes) the program instructions, transforming them into a series of control signals which activate other parts of the computer.[38] Control systems in advanced computers may change the order of some instructions so as to improve performance.
A key component common to all CPUs is the program counter, a special memory cell (a register) that keeps track of which location in memory the next instruction is to be read from.[39]
The control system's function is as follows—note that this is a simplified description, and some of these steps may be performed concurrently or in a different order depending on the type of CPU:
1. Read the code for the next instruction from the cell indicated by the program counter.
2. Decode the numerical code for the instruction into a set of commands or signals for each of the other systems.
3. Increment the program counter so it points to the next instruction.
4. Read whatever data the instruction requires from cells in memory (or perhaps from an input device). The location of this required data is typically stored within the instruction code.
5. Provide the necessary data to an ALU or register.
6. If the instruction requires an ALU or specialized hardware to complete, instruct the hardware to perform the requested operation.
7. Write the result from the ALU back to a memory location or to a register or perhaps an output device.
8. Jump back to step (1).
Since the program counter is (conceptually) just another set of memory cells, it can be changed by calculations done in the ALU. Adding 100 to the program counter would cause the next instruction to be read from a place 100 locations further down the program. Instructions that modify the program counter are often known as "jumps" and allow for loops (instructions that are repeated by the computer) and often conditional instruction execution (both examples of control flow).
The sequence of operations that the control unit goes through to process an instruction is in itself like a short computer program, and indeed, in some more complex CPU designs, there is another yet smaller computer called a microsequencer, which runs a microcode program that causes all of these events to happen.
Arithmetic logic unit (ALU)
Main article: Arithmetic logic unit
The ALU is capable of performing two classes of operations: arithmetic and logic.[40]
The set of arithmetic operations that a particular ALU supports may be limited to addition and subtraction, or might include multiplication, division, trigonometry functions such as sine, cosine, etc., and square roots. Some can only operate on whole numbers (integers) whilst others use floating point to represent real numbers, albeit with limited precision. However, any computer that is capable of performing just the simplest operations can be programmed to break down the more complex operations into simple steps that it can perform. Therefore, any computer can be programmed to perform any arithmetic operation—although it will take more time to do so if its ALU does not directly support the operation. An ALU may also compare numbers and return boolean truth values (true or false) depending on whether one is equal to, greater than or less than the other ("is 64 greater than 65?").
Logic operations involve Boolean logic: AND, OR, XOR and NOT. These can be useful for creating complicated conditional statements and processing boolean logic.
Superscalar computers may contain multiple ALUs, allowing them to process several instructions simultaneously.[41] Graphics processors and computers with SIMD and MIMD features often contain ALUs that can perform arithmetic on vectors and matrices.
Memory
Main article: Computer data storage
Magnetic core memory was the computer memory of choice throughout the 1960s, until it was replaced by semiconductor memory.
A computer's memory can be viewed as a list of cells into which numbers can be placed or read. Each cell has a numbered "address" and can store a single number. The computer can be instructed to "put the number 123 into the cell numbered 1357" or to "add the number that is in cell 1357 to the number that is in cell 2468 and put the answer into cell 1595". The information stored in memory may represent practically anything. Letters, numbers, even computer instructions can be placed into memory with equal ease. Since the CPU does not differentiate between different types of information, it is the software's responsibility to give significance to what the memory sees as nothing but a series of numbers.
In almost all modern computers, each memory cell is set up to store binary numbers in groups of eight bits (called a byte). Each byte is able to represent 256 different numbers (2^8 = 256); either from 0 to 255 or −128 to +127. To store larger numbers, several consecutive bytes may be used (typically, two, four or eight). When negative numbers are required, they are usually stored in two's complement notation. Other arrangements are possible, but are usually not seen outside of specialized applications or historical contexts. A computer can store any kind of information in memory if it can be represented numerically. Modern computers have billions or even trillions of bytes of memory.
The CPU contains a special set of memory cells called registers that can be read and written to much more rapidly than the main memory area. There are typically between two and one hundred registers depending on the type of CPU. Registers are used for the most frequently needed data items to avoid having to access main memory every time data is needed. As data is constantly being worked on, reducing the need to access main memory (which is often slow compared to the ALU and control units) greatly increases the computer's speed.
Computer main memory comes in two principal varieties: random-access memory or RAM and read-only memory or ROM. RAM can be read and written to anytime the CPU commands it, but ROM is pre-loaded with data and software that never changes, therefore the CPU can only read from it. ROM is typically used to store the computer's initial start-up instructions. In general, the contents of RAM are erased when the power to the computer is turned off, but ROM retains its data indefinitely. In a PC, the ROM contains a specialized program called the BIOS that orchestrates loading the computer's operating system from the hard disk drive into RAM whenever the computer is turned on or reset. In embedded computers, which frequently do not have disk drives, all of the required software may be stored in ROM. Software stored in ROM is often called firmware, because it is notionally more like hardware than software. Flash memory blurs the distinction between ROM and RAM, as it retains its data when turned off but is also rewritable. It is typically much slower than conventional ROM and RAM however, so its use is restricted to applications where high speed is unnecessary.[42]
In more sophisticated computers there may be one or more RAM cache memories, which are slower than registers but faster than main memory. Generally computers with this sort of cache are designed to move frequently needed data into the cache automatically, often without the need for any intervention on the programmer's part.
Input/output (I/O)
Main article: Input/output
Hard disk drives are common storage devices used with computers.
I/O is the means by which a computer exchanges information with the outside world.[43] Devices that provide input or output to the computer are called peripherals.[44] On a typical personal computer, peripherals include input devices like the keyboard and mouse, and output devices such as the display and printer. Hard disk drives, floppy disk drives and optical disc drives serve as both input and output devices. Computer networking is another form of I/O.
I/O devices are often complex computers in their own right, with their own CPU and memory. A graphics processing unit might contain fifty or more tiny computers that perform the calculations necessary to display 3D graphics[citation needed]. Modern desktop computers contain many smaller computers that assist the main CPU in performing I/O.
Multitasking
Main article: Computer multitasking
While a computer may be viewed as running one gigantic program stored in its main memory, in some systems it is necessary to give the appearance of running several programs simultaneously. This is achieved by multitasking i.e. having the computer switch rapidly between running each program in turn.[45]
One means by which this is done is with a special signal called an interrupt, which can periodically cause the computer to stop executing instructions where it was and do something else instead. By remembering where it was executing prior to the interrupt, the computer can return to that task later. If several programs are running "at the same time", then the interrupt generator might be causing several hundred interrupts per second, causing a program switch each time. Since modern computers typically execute instructions several orders of magnitude faster than human perception, it may appear that many programs are running at the same time even though only one is ever executing in any given instant. This method of multitasking is sometimes termed "time-sharing" since each program is allocated a "slice" of time in turn.[46]
Before the era of cheap computers, the principal use for multitasking was to allow many people to share the same computer.
Seemingly, multitasking would cause a computer that is switching between several programs to run more slowly, in direct proportion to the number of programs it is running, but most programs spend much of their time waiting for slow input/output devices to complete their tasks. If a program is waiting for the user to click on the mouse or press a key on the keyboard, then it will not take a "time slice" until the event it is waiting for has occurred. This frees up time for other programs to execute so that many programs may be run simultaneously without unacceptable speed loss.
Multiprocessing
Main article: Multiprocessing
Cray designed many supercomputers that used multiprocessing heavily.
Some computers are designed to distribute their work across several CPUs in a multiprocessing configuration, a technique once employed only in large and powerful machines such as supercomputers, mainframe computers and servers. Multiprocessor and multi-core (multiple CPUs on a single integrated circuit) personal and laptop computers are now widely available, and are being increasingly used in lower-end markets as a result.
Supercomputers in particular often have highly unique architectures that differ significantly from the basic stored-program architecture and from general purpose computers.[47] They often feature thousands of CPUs, customized high-speed interconnects, and specialized computing hardware. Such designs tend to be useful only for specialized tasks due to the large scale of program organization required to successfully utilize most of the available resources at once. Supercomputers usually see usage in large-scale simulation, graphics rendering, and cryptography applications, as well as with other so-called "embarrassingly parallel" tasks.
Networking and the Internet
Main articles: Computer networking and Internet
Visualization of a portion of the routes on the Internet.
Computers have been used to coordinate information between multiple locations since the 1950s. The U.S. military's SAGE system was the first large-scale example of such a system, which led to a number of special-purpose commercial systems such as Sabre.[48]
In the 1970s, computer engineers at research institutions throughout the United States began to link their computers together using telecommunications technology. The effort was funded by ARPA (now DARPA), and the computer network that resulted was called the ARPANET.[49] The technologies that made the Arpanet possible spread and evolved.
In time, the network spread beyond academic and military institutions and became known as the Internet. The emergence of networking involved a redefinition of the nature and boundaries of the computer. Computer operating systems and applications were modified to include the ability to define and access the resources of other computers on the network, such as peripheral devices, stored information, and the like, as extensions of the resources of an individual computer. Initially these facilities were available primarily to people working in high-tech environments, but in the 1990s the spread of applications like e-mail and the World Wide Web, combined with the development of cheap, fast networking technologies like Ethernet and ADSL saw computer networking become almost ubiquitous. In fact, the number of computers that are networked is growing phenomenally. A very large proportion of personal computers regularly connect to the Internet to communicate and receive information. "Wireless" networking, often utilizing mobile phone networks, has meant networking is becoming increasingly ubiquitous even in mobile computing environments.
Hardware
See also: History of computing hardware
The term hardware covers all of those parts of a computer that are tangible objects. Circuits, displays, power supplies, cables, keyboards, printers and mice are all hardware.
Hardware
First Generation (Mechanical/Electromechanical) Calculators Antikythera mechanism, Difference engine, Norden bombsight
Programmable Devices Jacquard loom, Analytical engine, Harvard Mark I, Z3
Second Generation (Vacuum Tubes) Calculators Atanasoff–Berry Computer, IBM 604, UNIVAC 60, UNIVAC 120
Programmable Devices Colossus, ENIAC, Manchester Small-Scale Experimental Machine, EDSAC, Manchester Mark 1, Ferranti Pegasus, Ferranti Mercury, CSIRAC, EDVAC, UNIVAC I, IBM 701, IBM 702, IBM 650, Z22
Third Generation (Discrete transistors and SSI, MSI, LSI Integrated circuits) Mainframes IBM 7090, IBM 7080, IBM System/360, BUNCH
Minicomputer PDP-8, PDP-11, IBM System/32, IBM System/36
Fourth Generation (VLSI integrated circuits) Minicomputer VAX, IBM System i
4-bit microcomputer Intel 4004, Intel 4040
8-bit microcomputer Intel 8008, Intel 8080, Motorola 6800, Motorola 6809, MOS Technology 6502, Zilog Z80
16-bit microcomputer Intel 8088, Zilog Z8000, WDC 65816/65802
32-bit microcomputer Intel 80386, Pentium, Motorola 68000, ARM architecture
64-bit microcomputer[52] Alpha, MIPS, PA-RISC, PowerPC, SPARC, x86-64
Embedded computer Intel 8048, Intel 8051
Personal computer Desktop computer, Home computer, Laptop computer, Personal digital assistant (PDA), Portable computer, Tablet PC, Wearable computer
Theoretical/experimental Quantum computer, Chemical computer, DNA computing, Optical computer, Spintronics based computer
Other Hardware Topics
Peripheral device (Input/output) Input Mouse, Keyboard, Joystick, Image scanner, Webcam, Graphics tablet, Microphone
Output Monitor, Printer, Loudspeaker
Both Floppy disk drive, Hard disk drive, Optical disc drive, Teleprinter
Computer busses Short range RS-232, SCSI, PCI, USB
Long range (Computer networking) Ethernet, ATM, FDDI
Software
Main article: Computer software
Software refers to parts of the computer which do not have a material form, such as programs, data, protocols, etc. When software is stored in hardware that cannot easily be modified (such as BIOS ROM in an IBM PC compatible), it is sometimes called "firmware" to indicate that it falls into an uncertain area somewhere between hardware and software.
Computer software
Operating system Unix and BSD UNIX System V, IBM AIX, HP-UX, Solaris (SunOS), IRIX, List of BSD operating systems
GNU/Linux List of Linux distributions, Comparison of Linux distributions
Microsoft Windows Windows 95, Windows 98, Windows NT, Windows 2000, Windows Me, Windows XP, Windows Vista, Windows 7
DOS 86-DOS (QDOS), PC-DOS, MS-DOS, DR-DOS, FreeDOS
Mac OS Mac OS classic, Mac OS X
Embedded and real-time List of embedded operating systems
Experimental Amoeba, Oberon/Bluebottle, Plan 9 from Bell Labs
Library Multimedia DirectX, OpenGL, OpenAL
Programming library C standard library, Standard Template Library
Data Protocol TCP/IP, Kermit, FTP, HTTP, SMTP
File format HTML, XML, JPEG, MPEG, PNG
User interface Graphical user interface (WIMP) Microsoft Windows, GNOME, KDE, QNX Photon, CDE, GEM, Aqua
Text-based user interface Command-line interface, Text user interface
Application Office suite Word processing, Desktop publishing, Presentation program, Database management system, Scheduling & Time management, Spreadsheet, Accounting software
Internet Access Browser, E-mail client, Web server, Mail transfer agent, Instant messaging
Design and manufacturing Computer-aided design, Computer-aided manufacturing, Plant management, Robotic manufacturing, Supply chain management
Graphics Raster graphics editor, Vector graphics editor, 3D modeler, Animation editor, 3D computer graphics, Video editing, Image processing
Audio Digital audio editor, Audio playback, Mixing, Audio synthesis, Computer music
Software engineering Compiler, Assembler, Interpreter, Debugger, Text editor, Integrated development environment, Software performance analysis, Revision control, Software configuration management
Educational Edutainment, Educational game, Serious game, Flight simulator
Games Strategy, Arcade, Puzzle, Simulation, First-person shooter, Platform, Massively multiplayer, Interactive fiction
Misc Artificial intelligence, Antivirus software, Malware scanner, Installer/Package management systems, File manager
Languages
There are thousands of different programming languages—some intended to be general purpose, others useful only for highly specialized applications.
Programming languages
Lists of programming languages Timeline of programming languages, List of programming languages by category, Generational list of programming languages, List of programming languages, Non-English-based programming languages
Commonly used Assembly languages ARM, MIPS, x86
Commonly used high-level programming languages Ada, BASIC, C, C++, C#, COBOL, Fortran, Java, Lisp, Pascal, Object Pascal
Commonly used Scripting languages Bourne script, JavaScript, Python, Ruby, PHP, Perl
Professions and organizations
As the use of computers has spread throughout society, there are an increasing number of careers involving computers.
Computer-related professions
Hardware-related Electrical engineering, Electronic engineering, Computer engineering, Telecommunications engineering, Optical engineering, Nanoengineering
Software-related Computer science, Desktop publishing, Human–computer interaction, Information technology, Information systems, Computational science, Software engineering, Video game industry, Web design
INRTODUCTION OF MICROSOFT EXCEL
Micro soft excel is a Spread Sheet. It is use to cerate result sheets, salary sheets, account statements, bank statements, vouchers and ledgers etc. We can solve the accounting and mathematical problems. It has so many formulas, graphs/charts etc.
Cell
A cell is instersection of row and column. It can also be derined as: a cell is basic unit of worksheet.
Row
A Row is collection of fields. Horizental information in a worksheet is called Row. There are 65536 rows in a single sheet.
Column
A column is vertical information in a worksheet. It is also doenoted by field. There are 256 columns in a single worksheet.
Worksheet
A worksheet consists of rwos and columns. Or a collection of rows and column is called worksheet.
Workbook
A collection of worksheets is called workbook. Workbook is a single documnet of microsoft excel.
Active cell
A cell in which you want to enter and edit data. A cell where there is a cursor is called active cell.
Operatign systems:
A operating system acta as corrdinator between user and computer Hardware. Most familiar names are Disk operating system (DOS), linux, Windows XP, 2000, 98,Me,and linux, Unix.
Microsoft Windows XP Features:
1. Windows XP?
Microsoft’s fastest, most reliable Windows operating system
Available in five editions: Home Edition, Professional Edition, Tablet PC
Edition,Media Center Edition,and 64-bit Edition
2. 2001 Microsoft Windows XP is released October 25, 2001.
3. (GUI)?
User interacts with menus and visual images such as icons and buttons
4. multitasking?
Working on two or more programs that reside in memory at same time
5. multiuser
Enables two or more users to run programs simultaneously
6. multiprocessing
Can support two or more processors running programs at same time
7. spooling?
Sending print jobs to buffer instead of directly to printer
8. Administering security
User name and password security
Record the successful and unsuccessful logon attempts
Passwords to files or folders
Files and Folder Permissions
9. network operating system
Allows users to share printer, Internet access, files, and programs on network
Administers security by establishing user name and password for each user
10. utility program
System software that performs maintenance-type tasks Also called utility
11. file manager?
Performs functions such as copying, renaming, deleting, and moving files
amount of used and free space on storage device
12. uninstaller
In Windows XP, uninstaller is in Add/Remove Programs in Control Panel
Removes a program and all associated files
13. disk scanner
Detects and corrects problems on hard disk or floppy disk
Searches for and removes unnecessary files
14. standard menu system: microsoft imposes strict formating guidelines for Windows progrms. All Windows XP programs must use a standard choices in all Windows XP programs.
15. Menu Commands: Commands are directions for the computer. When you invoke a command you are telling the computer to perform a specific task. In Windows XP , you enter commands by choosing them from menus listed on your screen.
16. Clipboard: The Clipboard is a temporary storage area. The Clipboard “holds” cut or copied information until you paste it or cut or copy new inforamation. You use the clipboard whenever you move or copy information in one program to another program.
17. Recycle Bin: Whenever you delete a folder or file from your computer, Windows places the item in the Recycle Bin. The Recycle Bin allows you to retrive items that you accidentally deleted of items you decided were important after all.
Computer Technology
Post a Comment