GNU was publicly announced on September 27, 1983, and today has a strong following.

GNU is...

an operating system

an extensive collection of computer software

free software

licensed under the GNU Project's own General Public License (GPL)

What else is GNU to you? Which tool is your favorite? Here are five great responses.

"My all-time favorite GNU tool is GCC, the GNU Compiler Collection. At a time when developer tools were expensive, GCC was the second GNU tool and the one that enabled a community to write and build all the others. This tool single-handedly changed the industry and led to the creation of the free software movement, since a good, free compiler is a prerequisite to a community creating software." —Dave Neary, Open Source and Standards team at Red Hat

"GNU Emacs was my first Unix application, and I used it for all my programming. While today I use different editors for different tasks (vi to edit system files, GNOME gedit to edit my HTML pages for my website, etc., I always go back to GNU Emacs when I write code. I have the muscle memory in my fingers that makes Emacs feel intuitive and a natural fit when I'm programming in C." —Jim Hall, creator of FreeDOS

"GCC is a standard compiler for most Unix-like operating systems. When I jumped into system programming many years ago, I invoked a language-specific driver program such as GCC for C, g++ for C++, etc. which interprets command arguments, calls the actual compiler, runs the assembler on the output, and then optionally runs the linker to produce a complete executable binary." —Daniel Oh, DevOps Evangelist at Red Hat

"I think that dd is my favorite GNU utility. I first learned about it and became interested in it when one of my mentors called it "disk destroyer," which made me want to know why it was called that. dd can be used for controlled reading of a data stream from any device in the /dev directory and then sending that data to other devices. Used like this it can be a great way to explore the content of hard drives and USB memory devices. dd can also be used to copy a bootable iso image from a hard drive to a USB device to create a bootable, live Linux image that is usable for demonstration or installation of Fedora, for example. The dd utility can provide the functional proof that everything is a file." —David Both, Community Moderator for Opensource.com

"It's not necessarily a tool, but one of the first things I install on every machine is GNU Backgammon. It's my go-to, quick game. It plays a really strong game and is completely open source. After one grueling morning of it completely humiliating me at a couple of games, I started griping about it in a meeting, saying I think it cheats at dice. One of my colleagues pulled up the source code that managed the dice roll and we all poured over it. We had to conclude that it had the most random code generator any of us had ever seen, and there was no way it cheated. I don't care though, I still think it cheats. (wink)" —Andy Thornton, Senior Software Associate at Red Hat

What's your favorite GNU tool? Or share your story about using GNU for the first time in the comments below.