When to use "ya había" and when to use "habia"?

Question

I'm trying to use the past perfect and in my textbook they use ya había.

What is that? What does it mean and how is it different from había?

Answer 1

"Había" is the past pefect as in "had". "Ya había" is as remarking that something was done before. Example: I had eaten (yo había comido). I had eaten already (yo ya había comido).