Additional resources

Git

Pro Git book (also covers basics)

Talks:

Tech Talk: Linus Torvalds on git (2.4M views) - A bit of history of git and the reasons why it was created
Learn Git In 15 Minutes - git basics

Probably more advanced stuff

Git Internals by John Britton of GitHub - CS50 Tech Talk - what git uses under the hood
Advanced Git Tutorial - as the title says
Advanced Git: Graphs, Hashes, and Compression, Oh My! - same

Speed-up your git workflow

git aliases
You can also set up zsh to show your branch name in prompt