CertiGuide to A+ (A+ 4 Real)  9  Chapter 5: The Linux Operating System

Chapter 5: The Linux Operating System 1 Linux Distributions

The roots of Linux date back to the late 1960’s with the creation of UNIX. Ken Thompson and Dennis Richie were two of the original creators of the UNIX operating system. The history of UNIX is well documented on the Web and can be found at http://www.bell-labs.com/history/unix/

In 1991 Linus Torvals, a student at the University of Helsinki wanted a copy of UNIX to run on his systems. However being a poor University student, he could not afford to buy a license. He decided to write his own copy of the UNIX kernel and posted his initial efforts on a news group hoping that others will contribute to his work. From this small beginning, Linux has grown to a full-fledged UNIX compatible operating system that is scalable from small-embedded systems to large clustered computers reaching supercomputer performance. The meteoric rise of Linux as an operating system has even been highlighted in a recent movie named Revolution OS. Local governments and businesses are starting to recognize the value of an operating system that they control, which gives the freedom to choose their computing environment and does not lock them into a single vendor. Recently the city adminstration of Munich, Germany decided to migrate with all its computer systems, servers and desktops, to the Linux operating system. Stories such as this are becoming very commonplace in the industry today.

The history of Linux⁸⁰ would not be complete without mentioning the efforts of Richard Stallman. In 1983, Richard founded the organization known as the Free Software Foundation (FSF). Richard believed that software should be freely available without restrictions from copying; from that idea, the Free Software Foundation and the GNU project were formed. From this effort, the GNU C compiler and many of the common UNIX utilities were written. Shortly after the free Software Foundation had started working on a UNIX like kernel, Linus and those helping him had finished the first Linux kernel. The combination of these two efforts has produced a fully functional operating system and basic utilities that was UNIX compatible.

One other significant contribution from Richard Stallman was a GNU general public license⁸¹ often known as the GPL.

There are three key points in the GPL:

• First, software licensed under the GPL must be published with the source code;
  
  
• Second, anyone who obtains a copy of the software can freely redistribute it; and
  
  
• Third, anyone can modify the software but any modifications must be made freely available.

Chapter 5: The Linux Operating System 1 Linux Distributions