I'm starting to put my own head into the vast world of DevOps myself and over the next few months I'll be sharing resources I find interesting and useful along the way.
As a starting point, you might want to look this short video:
and then see what the DevOps Resource Center has to provide. Here you'll find a short introduction to DevOps concepts in "What is DevOps?", down to the point introductions to Git and Agile available in "Learn Git" and "Learn Agile" and in "DevOps at Microsoft" you'll a vast set of short videos describing how Microsoft does DevOps.
For those of you working with SQL Server, you might also want to take a look at the video and the other resources in "DevOps using SQL Server".