First generation (1940-1956)vacuum tubes
the first generation of computer use vacuum tube for the circuitry and magnetic drum for the memory.A magnetic drum is a metal cylinder coated with magnetic iron-oxide material on which data and program can be stored. the first computer is the biggest and not simple computer , its hard to use it.the track on a magnetic drum are assigned to channel located around the circumference of the drum , forming adjacent circular bands that wind around the drum. a single drum can have up 200 tracks.
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 to perform operations, and they could only solve one problem at a time.the example of first computer is UNIVAC and ENIAC. The UNIVAC was the first commercial computer delivered to a business client. ENIAC (electronic numerical integrator and computer) is the first operational electronic digital computer.The ENIAC, weighing 30 tons, using 200 kilowatts of electric power and consisting of 18,000 vacuum tubes,1,500 relays, and hundreds of thousands of resistors,capacitors, and inductors, was completed in 1945.the ENIAC's field of application included weather prediction, atomic-energy calculations, cosmic-ray studies, thermal ignition,random-number studies, wind-tunnel design, and other scientific uses.
Second generation of computer(1956-1963)transistor
Transistor is a device composed of semiconductor material that amplifies a signal or opens or closes a circuit.Invented in 1947 at Bell Labs, transistors have become the key ingredient of all digital circuits, including computers.Prior to the invention of transistors, digital circuits were composed of vacuum tubes, which had many disadvantages. They were much larger, required more energy, dissipated more heat, and were more prone to failures.
It's safe to say that without the invention of transistors, computing as we know it today would not be possible.The transistor was invented in 1947 but did not see widespread use in computers until the late 50s. 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. the example of second generation computer is COBOL and FORTRAN.
Third generation of computer ( 1964-1971) integrated circuit
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.
Silicon is the basic material used to make the computer chips, transistors, silicon diodes and other electronic circuits and switching devices because its atomic structure makes the element an ideal semiconductor. Silicon is commonly doped, or mixed,with other elements, such as boron, phosphorous and arsenic, to alter its on which an integrated circuit is embedded. A typical chip is less than 1/4 square inches and can contain millions electronic component.Computers consist of many chips placed on electronic boards called printed circuit boards. There are different types of chips. For example, CPU chips (also called microprocessors) contain an entire processing unit, whereas memory chips contain blank memory.Semiconductor is a material that is neither a good conductor of electricity not a good insulator.
Fourth generation of computer ( 1971-now) microprocessor
The microprocessor brought the fourth generation of computers, as thousands of integrated circuits we rebuilt onto a single silicon chip.A silicon chip that contains a CPU. In the world of personal computers,the terms microprocessor and CPU are used interchangeably. At the heart of all personal computers and most workstations sits a microprocessor. Microprocessors also control the logic of almost all digital devices, from clock radios to fuel-injection systems for automobiles.The Intel 4004chip, 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.Abbreviation of central processing unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the processor or central processor, the CPU is where most calculations take place.On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor.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.
Fifth generation of computer ( now- ?) 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.Artificial Intelligence is the branch of computer science concerned with making computers behave like humans. The term was coined in 1956 by John McCarthy at the Massachusetts Institute of Technology.Currently, no computers exhibit full artificial intelligence . The best computer chess programs are now capable of beating humans. In May,1997, an IBM super-computer called Deep Blue defeated world chess champion Gary Kasparov in a chess match.Natural-language processing offers the greatest potential rewards because it would allow people to interact with computers without needing any specialized knowledge. You could simply walk up to a computer and talk to it. Unfortunately, programming computers to understand natural languages has proved to be more difficult than originally thought. Some rudimentary translation systems that translate from one human language to another are in existence, but they are not nearly as good as human translators.There are also voice recognition systems that can convert spoken sounds into written words, but they do not understand what they are writing. Even these systems are quite limited you must speak slowly and distinctly.
In the early of 1980s, expert systems were believed to represent the future of artificial intelligence and of computers in general. To date, however, they have not lived up to expectations. Many expert systems help human experts in such fields as medicine and engineering, but they are very expensive to produce and are helpful only in special situations.the hottest area of artificial intelligence is neural networks, which are proving successful in an umber of disciplines such as voice recognition and natural-language processing.There are several programming languages that are known as AI languages because they are used almost exclusively for AI applications. The two most common are LISP and Prologue.
