Computer history and generations

 The history of computers, computing and a timeline of the history of computers and early calculating machines has been included. Our timeline includes developments in the 1600's and their impact on computing. The development of the modern day computer was the result of advances in technologies and man's need to quantify. (The abacus was one of the first counting machines. Calculating machines were sold commercially before the advent of steel manufacturing technologies. Papyrus was something to write on, before we had paper. Writing was a way to record mathematical calculations.) This history of computers site includes the names of early pioneers of math and computing and links to related sites for further study.

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 monitorsand 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 handhelddevices.

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.

Computer Of Classification

There are four main classifications of computers: Mainframe computers, micro-computers mini-computers, and super-computers. Here is a brief breakdown of each:

* Mainframe computers *

Mainframe computers are extremely powerful and large computers that have the capacity to process the activity of multiple users at one time. Many other smaller, less powerful computers (otherwise known as terminals) are networked with the mainframe, meaning they are attached to the central mainframe computer. From here, the mainframe has the capability to process and store things that come from the connected terminals.

* Micro-computers *

These are most commonly known as personal computers and the computers that people use on a daily basis. Micro-computers contain their own microprocessor, which performs the job of a mainframe computer but with considerably less power as it is only required to process the activities of one machine.

Microprocessors became the most common type of processing equipment as they featured predominantly in personal computers. They had enough power to perform the basic recreational activities that people owning personal computers required. Typically, personal computers were used for playing music and movies as well as surfing the Internet and word processing amongst other things. Micro-computers are your typical laptop or desktop computers and are widely available at relatively affordable prices.

* Mini-computers *

These computers fall in the gap between micro-computers and mainframe computers. They possess much more power than a micro-computer, but not enough to perform the tasks of a mainframe computer. These were developed in the 60s and gradually became less expensive as time moved on and technology became more widely available.

* Super computers *

Super computers are the most powerful computers ever invented. They are used to process an enormous amount of terminal activity; even more than that of a mainframe computer. In fact, in the event of optimizing the performance of a mainframe computer, that will create a super computer.

Computer Components

Computers are made of the following basic components:

1. Case with hardware inside:
   

 Power Supply - The power supply comes with the case, but this component is mentioned separately since there are various types of power supplies. The one you should get depends on the requirements of your system. This will be discussed in more detail later

Motherboard - This is where the core components of your computer reside which are listed below. Also the support cards for video, sound, networking and more are mounted into this board.

Microprocessor - This is the brain of your computer. It performs commands and instructions and controls the operation of the computer.

Memory - The RAM in your system is mounted on the motherboard. This is memory that must be powered on to retain its contents.

Drive controllers - The drive controllers control the interface of your system to your hard drives. The controllers let your hard drives work by controlling their operation. On most systems, they are included on the motherboard, however you may add additional controllers for faster or other types of drives.

Hard disk drive(s) - This is where your files are permanently stored on your computer. Also, normally, your operating system is installed here.

CD-ROM drive(s) - This is normally a read only drive where files are permanently stored. There are now read/write CD-ROM drives that use special software to allow users to read from and write to these drives.

Floppy drive(s) - A floppy is a small disk storage device that today typically has about 1.4 Megabytes of memory capacity.

Other possible file storage devices include DVD devices, Tape backup devices, and some others.

Monitor - This device which operates like a TV set lets the user see how the computer is responding to their commands.

Keyboard - This is where the user enters text commands into the computer.

Mouse - A point and click interface for entering commands which works well in graphical environments.

These various parts will be discussed in the following sections.