Honestly, what isn't digital humanities?
But, in short, it's the interdisciplinary field of using digital tools, sources, and methods to do research in the humanities. It is a rapidly emerging and changing area of practice which you can skim the surface of here.
These are some of the core journals in DH. You may find browsing some of their articles useful.
These books and book series may also be useful as you start your DH journey:
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