receive, process and store data. O There are a lot of different components inside a computer, they all serve different purposes.
These components need to work together for the computer to work.O Today computer systems are found everywhere. Computers have become almost as common as televisions.O Computer systems are very widely used in many different environmentsi.e.Home:Computer that is used at home can be used to play games, watch films, internet browsing to obtain information or to purely for entertainment such as using social networking sites or as most people do keep their own personal information on their computer systems.Business:A company would have a lot of information they need to keep records of and computer based storage is more reliable than paper based.
Public Service:Public services such as Police departments use computer systems to keep a large storage of data, record of anyone’s personal information, monitor the streets through security cameras connected to their computers. HISTORY:O The computer as we know it today had its beginning with a 19th century English mathematics professor name Charles Babbage. O He designed the Analytical Engine and it was this design that the basic framework of the computers of today are based on. O The progression in hardware representation of a bit of data:o Vacuum Tubes (1950s) – one bit on the size of a thumb.o Transistors (1950s and 1960s) – one bit on the size of a fingernail.o Integrated Circuits (1960s and 70s) – thousands of bits on the size of a hand.
o Silicon computer chips (1970s and on) – millions of bits on the size of a finger nail. O The progression of the ease of use of computers:o Almost impossible to use except by very patient geniuses (1950s);o Programmable by highly trained people only (1960s and 1970s);o Useable by just about anyone (1980s and on).O To see how computers got smaller, cheaper, and easier to use. A computer based upon two important components.Hardware & Software.
HARDWARE:All the physical components and peripherals are called Hardware. A hardware can be seen and touched. I.e. Mouse, Keyboard, Monitor, Cables etc. SOFTWARE:O A software is a program or set of programs which are used to communicate with the hardware. A software can be seen but not touched.
O Software is a general term for the various kinds of programs used to operate computers and related devices.I.e. Microsoft Windows, Facebook, Google (Larry Page & Sergey Brin), MS Office etc. PARTS OF COMPUTER:There are 4 main parts of the computer.
O INPUT DEVICESO PROCESSOR / CPUO OUTPUT DEVICESO STORAGE DEVICES INPUT DEVICES:These are the devices which are used to sent instruction to the computer.i.e. O KeyboardO MouseO ScannerO Joy sticks etc. PROCESSOR:Processor is a device used to convert the input data into information and create an output. ??? CPU (Central Processing Unit):CPU is the collection of devices which process the input data to get an output. The central processing unit (CPU) converts data to information.
STORAGE DEVICES:These are the devices used to save data either permanent or temporarily.There are 2 basic types of storage devices.O RAM (Random Access Memory)O ROM (Read Only Memory) RAM (Random Access Memory):It is temporary memory used to process the data. When you power off your computer the data stored in RAM is deleted.
Increasing the amount of RAM memory can provide more efficiency to work for a computer. ROM (Read Only Memory):It is a permanent memory which is used to store the data. When you power off your computer the data stored in ROM doesn’t remove but exist in the form of same data.Increasing the amount of ROM memory can provide more space to store your data i.e.
O Hard DiskO Flash/USB Drive O CD/Floppy Drive OUTPUT DEVICES:These are the devices which gives the user interface as a result or through which the processed instructions could be seen given by input devices.i.e.O Monitor/LCD/LEDO PrintersO Multimedia etc.
(1.2)HARDWARE COMPONENTS:Motherboard:A Motherboard is the main printed circuit board (PCB) found in computers. It holds and allows communication between electronic components of a system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals. POWER SUPPLY:A power supply unit (PSU) converts mains AC to low-voltage regulated DC power for the internal components of a computer. MAIN MEMORY / RAM (Random Access Memory):It is temporary memory used to process the data. When you power off your computer the data stored in RAM is deleted. Increasing the amount of RAM memory can provide more efficiency to work for a computer. PORT:A computer port is the point from where the data is to be travelled to different components inside the computer.
i.e. O USB portO Printer portO COM portO VGA port ACCELERATED GRAPHICS PORT (AGP):The Accelerated Graphics Port (AGP) is a high-speed point-to-point channel for attaching a video card to a computer system, primarily to assist in the acceleration of 3D computer graphics. It was originally designed a successor to PCI-type connections for video cards. PRINTERS:O Accepts text and graphic output from a computer and transfers the information to paper.
O Personal computer printers can be distinguished as impact or non-impact printers. ?IMPACT PRINTER:O Early impact printers worked something like an automatic typewriter, with a key striking an inked impression on paper for each printed character.O The dot-matrix printer was a popular low-cost personal computer printer. It’s an impact printer that strikes the paper a line at a time. NON-IMPACT PRINTER:O The best-known non-impact printers are the inkjet printer, of which several makes of low-cost color printers are an example, and the laser printer.O he inkjet sprays ink from an ink cartridge at very close range to the paper as it rolls by. The laser printer uses a laser beam reflected from a mirror to attract ink (called toner ) to selected paper areas as a sheet rolls over a drum. PLOTTERS:O A plotter is a computer hardware device much like a printer that is used for printing vector graphics.
Instead of toner, plotters use a pen, pencil, marker, or another writing tool to draw multiple, continuous lines onto paper rather than a series of dots like a traditional printer. O Though once widely used for computer-aided design, these devices have more or less been phased out by wide-format printers. Plotters are used to produce a hard copy of schematics and other similar applications. CAMERAS:O A webcam is a video camera that feeds or streams its image in real time to or through a computer to a computer network. O When “captured” by the computer, the video stream may be saved, viewed or sent on to other networks via systems such as the internet, and emailed as an attachment. SCANNERS:O A scanner is a device that captures images from photographic prints, posters, magazine pages, and similar sources for computer editing and display. Scanners come in hand-held, feed-in, and flatbed types and for scanning black-and-white or color KEYBOARD AND MOUSE:O A computer mouse is a hand-held pointing device that detects two-dimensional motion relative to a surface. This motion is typically translated into the motion of a pointer on a display, which allows a smooth control of the graphical user interface.
O In computing, a computer keyboard is a typewriter-style device which uses an arrangement of buttons or keys to act as a mechanical lever or electronic switch. Following the decline of punch cards and paper tape, interaction via tele printer-style keyboards became the main input device for computers. MONITORS:O Definition of: monitor (1) A display screen used to provide visual output from a computer, cable box, video camera, VCR or other video generating device. O Computer monitors use CRT and LCD technology, while TV monitors use CRT, LCD and plasma technologies. See analog monitor, digital monitor and flat panel display. DISPLAY ADAPTERS:O A plug-in card in a desktop computer that performs graphics processing. Also commonly called a “graphics card” or “video card,” modern display adapters use the PCI Express interface, while earlier cards used PCI and AGP.
MULTIMEDIA DEVICES:O Multimedia devices are electronic media devices used to store and experience multimedia content. Multimedia is distinguished from mixed media in fine art; for example, by including audio it has a broader scope. PLUG AND PLAY COMPONENTS:O In computing, a plug and play (PnP) device or computer bus, is one with a specification that facilitates the discovery of a hardware component in a system without the need for physical device configuration or user intervention in resolving resource conflicts.NETWORK DRIVER: Software that activates the actual transmission and receipt of data over the network. GRAPHIC DRIVER:A driver is software written for a specific operating and color scheme of computer. MODEM: An electronic device that makes possible the transmission of data to or from a computer via telephone or other communication lines.
OPTICAL DRIVE:An optical drive is a type of computer disk drive that reads and writes data from optical disks through laser beaming technology i.e.CDs, DVDs and Blu-ray disks. SOFTWARE COMPONENTS: OPERATING SYSTEM:O An operating system is a program used to operate the hardware of a computer system. Without an operating system, a computer is nothing but a dead body. O An operating system (OS) is the program that, after being initially loaded into the computer by a boot program, manages all the other programs in a computer. Some of the operating systems areO WindowsO MacO LinuxO Solaris O Android APPLICATION PROGRAM:O Application programs use the services of the computer’s operating system and other supporting programs.
O The application programs make use of the operating system by making requests for services through a defined application program interface (API). O In addition, users can interact directly with the operating system through a user interface such as a command line or a graphical user interface (GUI). Some of the application programs are i.e.
O Word processorsO Database programsO Web browsers development toolsO Drawing, paintO Image editing programsO Communication programs UTILITY PROGRAMS:O A utility program is used to perform a very specific task. Usually related to managing system resources. O Utility software is system software designed to help analyze, configure, optimize or maintain a computer. It is used to support the computer infrastructure in contrast to application software, which is aimed at directly performing tasks that benefit ordinary users.Operating systems contain a number of utilities for managing resources likeO Disk drivesO PrintersO Network devicesO ServersO Other devices.
SPECIAL PURPOSE SOFTWARE:O Special purpose application software is a type of software created to execute one specific task. For example a camera application on your phone will only allow you to take and share pictures.O Another example would be a chess game, it would only allow you to play chess. LIBRARY PROGRAM:O A library is a collection of non-volatile resources used by computer programs, often to develop software. O These may include configuration data, documentation, help data, message templates, pre-written subroutines, classes, values or type specifications. In IBM’s OS/360 and its successors they are referred to as partitioned data sets. TRANSLATOR PROGRAM:O A translator or programming language processor is a computer program that performs the translation of a program written in a given programming language into a functionally equivalent program in another computer language (the target language), without losing the functional or logical structure of the original code (the “essence” of each program). SPECIAL PURPOSE SOFTWARE:O Special purpose application software is a type of software created to execute one specific task.
O For example a camera application on your phone will only allow you to take and share pictures. O Another example would be a chess game, it would only allow you to play chess. BE-SPOKE SOFTWARE:O Be-spoke software is a software that is specially developed for some specific organization or other user. O As such, it can be contrasted with the use of software packages developed for the mass market, such as commercial off-the-shelf (COTS) software. O Existing free software. (1.
3)There are three basic kinds of computers.O Analog ComputersO Digital ComputersO Hybrid Computers ANALOG COMPUTERS:Analog computers are the first computers being developed. It measures continuous changes in some physical quantity e.g. The Speedometer of a car measures speed, the change of temperature.i.
e.O Analog watchO Speed meter etc DIGITAL COMPUTERS:A digital computer can be used to process numeric as well as non-numeric data based upon the concept of BINARY NUMBERS (0,1). The results of digital computers are more accurate than the results of analog computers.i.e.O ComputerO Mobile phonesO Digital speed meters etc HYBRID COMPUTERS:Hybrid computers are the combination of digital computers and analogs computer. The results of digital computers are more accurate than the results of analog computers.
The use of these computers are in petrol pumps, atomic centers, satellite communication and other critical areas. CLASSIFICATION OF DIGITAL COMPUTERS:Digital computers may be classified in four major categoriesO Micro computersO Mini computersO Mainframe computersO Super computer Microcomputers:These computers can be used for small data processing jobs of bigger companies or serve as complete computer systems for small firms.i.e.O Desktop computersO LaptopsO Mobile phones etc Mini computers:Mini computers are very popular among medium sized companies.
Mini computers offer facilities for faster processing of voluminous information.i.e.
O Small sized server machinesO The computers used in cooperate offices Mainframe computers:The mainframe popularity has fallen due to emergence of microcomputers and popularity of client server technology.Mainframes are bigger computers, capable of handling data processing needs. These servers are used in i.e.O Head office of a bankO A big multinational company etc Super computer:Super computers are quite expensive and bigger in size. They cost somewhere around 10-30 million dollars depending upon the configuration.These computer are being used in big data centersi.e.O NASAO SatellitesO Atomic plants etc Comparison in types of computers