Updated: Dec 14, 2020
They've uploaded ancient texts so you can read them as if flipping through the original pages. This is an amazing tool for history writers who can now peruse original documents without travel and permissions. It's also great for historical fiction writers who may want to actually read the book they have a character reading.
They also have collections from other libraries with collections not quite so old. For example, I opened California Digital Library and found this:
Being called a Goody Two Shoes was a slur when I was a kid - I never knew it originated in a children's story.
Sometimes I love the internet.