Computer is one of the latest and greatest invention by man which changed the whole world to a global village by various means. In today’s world the computer device is very popular but only few people know about the history of computers. The computers were widely used after 1964. Due to research work on computers various types of computers, they vary in respect with size,work and usability . There are totally five generations of computers known till today.
The First generation computers used the vacuum tubes for circuitry and magnetic drums for memory and these were very big in size. 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.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. Feature of the first generation computers:
- They were fastest calculating divices of their time.
- They were too bulky in size, requiring large rooms for installation.
- Due to low mean time between failures, these computers required constant maintenance.
In this Generation Transistors replaced vacuum tubes. 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 Computers. On software front 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. Features of Second-generation computers:
- They were more than ten times faster than first generation computers.
- They were smaller than first generation computers and required small space.
- They consumed less power than first generation computers.
Third Generation This generation is known for the Integrated Circuits which 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. 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 common people because they were smaller and cheaper than their predecessors. Features of Third Generation Computers:
- They were more powerful than second generation computers. They were capable of performing about 1 million instructions per second.
- They were smaller than second generation computers requiring smaller space.
- They were general purpose machines suitable for both scientific and commercial applications.
In this generation of computers the microprocessors were brought, 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.Overnight computers become incredibly compact. They became inexpensive to make, and suddenly it became possible for anyone to own a computer. Features of fourth generation computers:
- PC’s were smaller and cheaper than mainframes or minicomputers of third generation.
- They consumed less power than third generation computers.
- They were faster and larger primary and secondary storage as compared to third generation computers.
- They were general purpose machines.
Fifth Generation 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. Features of fifth generation computers:
- Portable PCs are much smaller and handy than PCs of fourth generation allowing users to use computing facility even while travelling.
- They consume less power than their predecessors do.
- Fifth generation desktop PCs and workstations are several times more powerful than PCs of fourth generation.
Today we use various types of computer like smartphones, laptops, tablets, notebooks,etc. It is interesting to know that we use computers every day from calculator to highly built machines.