Sunday, October 24, 2010

The appearance of the PC (personal computer)

Ted Hoff at Intel invented the microprocessor in 1971. At the same time, IBM invented the floppy disk as a convenient, small and cheap means of storing computer data. Now, using a single processor chip, complemented by a few memory chips and input/output devices, it was possible to create a working micro-computer. The first commercially available computer kit (the MITS Altair) duly appeared in 1975, and the Commodore PET computer was the hit of 1977. A period of intense further development of the microprocessor chip took place at Intel. The 8086 chip was released in 1979 and the 8088 in 1980.

Based on the Intel 8088 microprocessor, the IBM PC (personal computer) appeared in August 1981 . This set the standard for PCs as we know them today. The IBM PC incorporated the DOS (disk operating system) software developed by the Micro-Soft company (later renamed Microsoft) which had been set up by Bill Gates and Paul Allen in 1975. By 1983, a new version of the IBM PC, the IBM PC XT, included a hard disk for storage of data.

Apple Computer, founded by Steve Jobs and Steve Wozniak in 1976, introduced the Macintosh computer in 1984. It revolutionised personal computing with the graphical user interface (GUI), the use of a mouse to ‘point and click’ and the opening of different ‘windows’ for different tasks. Microsoft quickly reacted by introducing a new operating system software, Microsoft Windows, in 1985. The ‘look and feel’ of Microsoft Windows were so similar to the Macintosh operating system that it led Apple Computer to file a lawsuit.

The role of UNIX in the development of the Internet

In 1969, the UNIX computer operating system was developed by Ken Thompson of AT&T Bell Laboratories. It has turned out to be one of the most powerful and widely accepted computer operating systems for computer and telephone exchange systems requiring multitasking and multi-user capabilities.

Standard UNIX commands allow for access to computer files, programs, storage and other resources. Encouraged by the hardware volumes purchased by AT&T (American Telegraph and Telephone company), UNIX was quickly adopted by many computer manufacturers as their standard operating system, so that computer programs and other applications written for UNIX could easily be ported (i.e., moved with only very few changes) from one computer system to another.

Most importantly for the development of the Internet, one of the participants in the ARPANET, the University of California in Berkeley, at the request of DARPA, wrote an extension to UNIX to incorporate the newly developed TCP/IP protocols. This version of UNIX was called UNIX 4.2BSD(Berkeley System Distribution). It was immediately used in the ARPANET and was released to the public domain in 1983. It opened the door for rapid further development of applications for file transfer between computers and for a more-widely standardised form of email. The embedding of TCP/IP within UNIX also made UNIX servers the natural choice of hardware for web servers, which would appear later.

Understanding Protocal and Network Standards

A standard is an agreed-upon definition of a protocol. In the early days of computer networking, each computer manufacturer developed its own networking protocols. As a result, you weren’t able to easily mix equipment from different manufacturers on a single network. Then along came standards to save the day.

Standards are industry-wide protocol definitions that are not tied to a particular manufacturer. With standard protocols, you can mix and match equipment from different vendors. As long as the equipment implements the standard protocols, it should be able to coexist on the same network. Many organizations are involved in setting standards for networking. The five most important organizations are:-

  1. American National Standards Institute (ANSI): The official standards organization in the United States. ANSI is pronounced An-See. (
  2. Institute of Electrical and Electronics Engineers (IEEE): An international organization that publishes several key networking standards; in particular, the official standard for the Ethernet networking system (known officially as IEEE 802.3). IEEE is pronounced Eye-triple-E. (
  3. International Organization for Standardization (ISO): A federation of more than 100 standards organizations from throughout the world. If I had studied French in high school, I’d probably understand why the acronym for International Organization for Standardization is ISO, and not IOS. (
  4. Internet Engineering Task Force (IETF): The organization responsible for the protocols that drive the Internet. (
  5. World Wide Web Consortium (W3C): An international organization that handles the development of standards for the World Wide Web. (