If your job involves some aspect of programming, I recommend that you read Pro Git. Git is the new standard for adding version control to your files, and given its ubiquity the payoff of learning the basics is huge. They negative payoff of not learning it is huge as well (think of the hundred hours wasted of your life looking for the same Stackoverflow post about git).

Pro Git makes a great job teaching basic, intermediate and advanced topics (it even has pictures!). As with everything, Pareto’s Law applies: 20% of the book contains 80% of the content. Hence, if you want to become proficient in git, you just need to read chapter 1, 2 and 3. With this, you will master all that you need to know for your day to day life: how to set a git repository, share code, create branches, switch between branches, merge branches, solve merge conflicts, etc.

The rest of the chapters contain very useful tricks as well. I want to highlight Ch. 4, were you will learn different ways to organize your team around git; and Ch. 7 in which you will learn some obscure but useful commands: stash, grep, reset and rebase. Also the discussion about the submodules is a must, specially for senior developers.

Finally I would like to mention that the book is free! So there is no excuse not to get it and master it.