Explaining GitHub

April, 2011

GitHub is well beyond being just another startup, but I still find myself explaining over and over again what it is that GitHub actually does. My brother posted this link on Facebook the other day with a comment that he still has no idea what we do, but has so far surmised that it has “something to do with a cat and an octopus”.

So here, presented in two parts, is the crash course for the layman:

Part 1: Git

We have to start with Git. Git and GitHub are two different things. Git is a version control system. You don’t need to know anything about it other than it is amazing.

Okay, maybe I’ll tell you a little more than that. If you have ever typed a paper into a computer (or written one by hand) you have probably used a low fidelity form of version control. Say you are working on a big paper and at certain points you want to save off a version or draft. You might do this for many reasons. Maybe it is an important paper and you want to put a copy somewhere else safe. Maybe you add a 01 to the filename and later a 02 and so on (or you might use today’s date ImportantPaper_4_13_2011.txt). Maybe you need to turn in a draft or pass a draft off for editing. These activities are all analogous to creating a snapshot of what your paper looks like at a certain point in time and saving it off. Another good example of why having snapshots is important is if you are going to completely re-write your conclusion. Having a saved version of your old conclusion lets you go back to it at any time to see what you wrote or even to revert back because your new conclusion turned out to be a bad idea.

Software developers are usually focused on code instead of papers, but they have the same problems. You need to be able to quickly and easily take snapshots of the current state of your code base (along with some comments about that revision) and have the ability to come back to that point in history at any time. You might also want to compare the current state of your code with any previous state. Programmers call the solution to this problem version control. Just as you could write your paper in any number of document editing systems (Word, Pages, text files, Quark, LaTeX, etc) there are many different version control systems. Git is one of those systems. Developers write programs in a variety of computer languages and these programs are sort of like big papers, but vastly more complex. Having the ability to take snapshots frequently and travel back in history to see how a code file changed over time is an essential activity.

If you are really interested in learning more about Git you can download and learn about it here. I would also highly recommend my friend Scott Chacon’s book Pro Git.

If you have stuck around just for the Octocats, then I suggest you head over to the octodex until part 2 comes out.

Tim's Avatar Building GitHub since 2011, programming language connoisseur, San Francisco resident, aspiring surfer, father of two, life partner to @ktkates—all words by me, Tim Clem.