25th August, 1991 was the day when Linux was conceptualised by a student named Linus Torvalds at the University of Helsinki. It all started when Torvald posted a question on the newsgroup comp.os.minix as what would they like to see most in minix. Minix is an operating system, which was based on Unix , which in 1991 was already 20 years old and Linux was developed by keeping Minix as the base. It's a long chain, right? All the three operating system viz Unix, Minix and Linux are open source, since the time of their existence.
Happy Birthday, Linux!
Linux derived its name accidentally. Torvald wanted to name it “Freax”, but a friend who ran the FTP server named Torvalds' source code download directory as 'linux' and from that moment the name stuck. Linux was developed by using the free GNU software development toolchain, compiler, user space commands and other tools which were originally developed by Richard Stallman in 1984. Linux quickly gained popularity amongst developers and got converted into a fully fledged operating system supporting thousands of software applications. It is still getting continuously developed by thousands of developers all around the world who contribute their respective source codes.