What do you need to know? Java Enterprise Edition. That’s the simple answer.
If you read between the lines what I’m really saying is: “You better make sure you really don’t give a flying toss about technology and don’t care about how frustrating what you spend most of your day doing is.”

Remember a long time ago, at the dinner table, when your kid brother mashed together a bunch of food that really should not have been mashed together — chicken, jello, gravy, condiments, corn, milk, peas, pudding, all that stuff — and proceeded to eat it? And loved it! And then your crazy uncle, having seen the look of disgust on your face, said: “it all goes to the same place!” Remember that? No? Then you were probably the one shoving nasty shit into your face, but the important thing to understand here is that your uncle is crazy. And so is Git.