But Linux is not all cakewalk. Watch your step, for it is no merry stroll we take. It is more of journey, which will lead you right into the innards of your O/S. So lets start at the beginning--the history of Linux.
There was a time, when there was no Windows, no Microsoft and believe it or not, computers still existed. It was the age of Unix. A mostly command line based operating system which was robust, stable, mostly crash free and yet costly. Linus Torvalds (Father of Linux), at that time, was a University student from Helsinki, Finland. He had a PC but could not afford Unix and since CD ROMs were still in the research stage, piracy had not become the orde of the day. And although Unix was ideal for PCs that were networked or connected with each other, it was too big for a standalone PC an average student had. So Linus decided to make his own o/s.
Back then, there already existed a small version of Unix called Minix that was not very popular. Linus made a new o/s of his own and named it Linux for his own name. In August 1991, he posted the o/s and its source-code on the still budding Internet with a request to anyone who may download it to make suggestions and/or improvements in the o/s and mail them back to him. A wise move.
And nothing had prepared him for the number of responses received. People who surfed the Net in those days were mostly computer science students and Linus had made something everyone needed. What’s more, everyone could modify the o/s to personalize it. Soon hundreds of emails started pouring in. And the Linux community had been formed.
What propelled Linux was that it was an open source O/S. i.e. the source code of the operating system was not only available to anyone who wanted it, but he/she could modify it. The only(and at that time just moral not legal) obligation was that the individual had to email the change to Linus and he would incorporate it into the Official version of Linux if he felt it was good.
As the Internet grew in size, thousands of programmers across the world started working on Linux, each one either adding something new or correcting a flaw somewhere. Therefore all the good things got included in the official version and soon Linux flowered into a full-fledged Operating System.
Later of course, Linus started distributing Linux under the GPU or General Public License. This entitles a user to change the source code of the O/S and distribute it, even commercially, provided he agrees to publish the change. In return he gets a copyright to that change. And this is how it is today.