The three Horseman of Operating system are not too old but they were created almost 30 years ago. At first they don't much to computer but later most of the software Company depend of the Operating system. At first Computer were use to calculate but later ....
The computer scientist prove that using the programming computer can be operate easily and use to do more thing. So many Company like philps, Dell , HP started to building Computer and Operating system. IBM was also involved. In the later 1980's IBM told Bill gates a young computer programmer to build a Operating system for them. Bill gates wasn't involved in IBM but his mother has connection with the IBM. By using this connection IBM hire Bill gates that they will use OS that bill gates will provide. In this competition Stev Jobs and Steve Wozniak was one of them they think this is great opportunity to build and sell computer to general people at fair price since Computer was to expensive So they create a company name Apple In 1976.
In the year 1984 Apple first launch the MacOS for Macintosh Computer. It was user friendly from the previous computer and it was lightweight for the system but it was also has down side for the consumer. To use the MacOS they had to buy the Macintosh Computer other wide they can't use the OS or use the OS in other computer. So next year in 1985 Bill gates create a company name Microsoft create their operating system for IBM but at first but later they develop a alternative version for other computer and because of this microsoft get the 90% of the market of the computer and surpass Apple. But in early time of Microsoft they made software for Apple.
After the Software battle microsoft and apple has good market and were earning good. but the problem was they were all paid and none of them was free. The international copy write law and lack of internet there was not crack and even it was cracked later it was filled with virus and back-door spy wire. So for normal budget consumer it was difficult.
In 1991 a Finnish software engineering student named Linus Torvalds developed an open-sourced kernel and Operating system for free. Linus open source the source code as result many developer and organization copy the code and develop a Operating system and released it. The main thing for linux is famous for are security and light weight. Mostly all of the Linux based Operating system. Since it is open-sourced any bug and can be found easily in the OS as result in the early 90's and 20's most of the developer who developed and fixed bugs of linux kernel where hackers. At first it was difficult to operate linux but at present it is very easy to operate some time problem occurs but it easy to fix.