Computer

Computer
A computer is a system for processing information. It receives data from various sources and combines it with instructions to produce the desired results. Early computers in the 1960s used punch cards for inputs and produced results on monitors or special computer paper. Apple produced the first consumer computer with a graphical user interface in 1976. With the more powerful processors available today, you can add other items to expand the computer's functionality. Connected to networks and the Internet, computers can receive, process and send information in many different ways.

Input

Modern computers receive their data through various components. When you post a message on a social networking site, the computer first accesses the website through its Internet connection via the modem. You use your keyboard to enter the message text. If you want to post a picture or video clip, you may take that from a data storage component such as a hard drive, from a CD or DVD via your computer's optical drive or from a memory stick or card via a USB port or card reader. Throughout this input process your mouse clicks on icons and buttons to deliver commands.

Processing

Before it can appear in your message, the computer must process the input data and change it into the correct code and format. The computer carries out the processing inside the main computer box or central processing unit. The CPU has plugs for all the input and output parts and contains the microprocessor, memory and network, USB, video and audio interfaces on the motherboard or on separate electronic cards. The CPU also includes the hard drive, which stores programmed instructions in the computer software on the drive. The CPU uses these instructions to process your input in the microprocessor, temporarily storing information in the memory before sending it to the interfaces for output.

Output

Once processed, your message is ready for posting. The CPU sends it to the network interface, which sends it to the modem -- or first to your router, either through a cable or a wireless connection, and the router directs it to the modem. The modem sends it out to the website and your message appears. Your computer shows you this process by displaying it on your monitor via the video interface. If you want to print out your message, your CPU will send it to the printer via the USB interface. If you want to play your video, your CPU will display the picture on the screen via the video interface and send the sound to the speakers via the audio interface.

Peripherals

Additional input/output devices can extend the computer's functions. Microphones, webcams and scanners help input audio signals and video or graphics. External drives store your data outside the CPU and let you transfer it to other computers. Projectors output large images for viewing in a group. These peripherals typically work via the USB interface and most computers have several USB ports to allow for the connection of various peripheral devices.

References

• Windows: Parts of a Computer
• The Computer Technology Documentation Project: Computer Hardware
• George Mason University: History of Computing

Computer hardware:
It is the collection of physical elements that constitutes a computer system. Computer hardware refers to the physical parts or components of a computer such as the monitor, mouse, keyboard, computer data storage, hard drive disk (HDD), system unit (graphic cards, sound cards, memory, motherboard and chips), etc. all of which are physical objects that can be touched.

Computer Software:

Software is any set of machine-readable instructions that directs a computer's processor to perform specific operations. A combination of hardware and software forms a usable computing system.

What Are the Five Generations of Computers?

In this Webopedia reference article you'll learn about each of the five generations of computers and the technology developments that have led to the current devices that we use today. Our journey starts in 1940 with vacuum tube circuitry and goes to the present day -- and beyond --  with artificial intelligence.

First Generation (1940-1956) Vacuum Tubes

The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions.
First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts.
The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951.

Second Generation (1956-1963) Transistors

Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use in computers until the late 1950s. The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation predecessors. Though the transistor still generated a great deal of heat that subjected the computer to damage, it was a vast improvement over the vacuum tube. Second-generation computers still relied on punched cards for input and printouts for output.
Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.
The first computers of this generation were developed for the atomic energy industry.

Third Generation (1964-1971) Integrated Circuits

The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers.
Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.

Fourth Generation (1971-Present) Microprocessors

The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer—from the central processing unit and memory to input/output controls—on a single chip.
In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more everyday products began to use microprocessors.
As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.

Fifth Generation (Present and Beyond) Artificial Intelligence

Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.

DID YOU KNOW...?

An integrated circuit (IC) is a small electronic device made out of a semiconductor material. The first integrated circuit was developed in the 1950s by Jack Kilby of Texas Instruments and Robert Noyce of Fairchild Semiconductor.