Always do! Although as a side-note while we're on that subject - there were a surprising number of people out there who were pushing sensitive information up to their repositories (often public repositories); things like server keys, API access credentials, password files, etc... were ending up in repositories. So you might even say "have you sanitized your git commits today" as well. (For this you can include a ".gitignore" file at the root of the project and/or within any given directory in the tree and tell git to ignore file(s) thereby never allowing those to make their way into the repository).

Git itself is a version control system - meaning it keeps track of a file or set of files as updates and changes occur; rather than saving a full backup of a file every time some line(s) of code are changed, it can take a 'diff' (difference) between the two and track who made those new changes, and when. This lets you roll-back to previous snapshots of a file if something new was added that broke functionality, and it makes it very good for managing large projects with a lot of developers (since you can literally pinpoint and 'blame' who created some bad code that broke stuff). GitHub itself is simply a cloud-based service offering repository hosting (storage containers if you will) that host your programming projects. There are a lot of others, BitBucket might be the largest competitor I would say. BitBucket also integrates with other services the parent company (Atlassian) offers such as JIRA (project management and issue tracking). You can also host your own repositories on a server in-house and use Git to push to your own server and not need GitHub. GitHub is free to use if you want to host your own code as open-source and publicly available, but if you need private repositories such as for proprietary code you need to pay for those repositories.

re·tard verb riˈtärd/ 1. delay or hold back in terms of progress, development, or accomplishment.

GitM for people who hold back progress and development... I don't see what's so offensive. Ohhhh .... they assumed that it was targeted at a specific group of "mentally handicapped" individuals - they're the ones injecting the offensive nature to a very legitimate word by banning it. Maybe we should complain that Git itself is offensive to individuals who have had family members decapitated in accidents for their use of "Detached Head", or maybe we need to ban MongoDB for being "$exist".

Or all these shitty people out there complaining about this kinda stuff can stop being complaining twats and not get offended over everything. Everyone on Github should go and throw the word "retard" into their repos somewhere (or everywhere) to prove a point. Use it however you want - maybe "Hey we need to fix this bug or it will retard our progress" ... legitimate use of the word, let's see how they react.