I ran across this Wikipedia book while working on one of the data structures posts for today.
I think you may find it useful but some cautions:
First, being a collection of Wikipedia articles, it doesn’t have a consistent editorial voice. That is more than being fussy, the depth and usefulness of explanations will vary from article to article.
Second, you will find topics that are “stubs,” and hence not very useful.
Third, I think with the advent of Neo4j, Grelim, Cypher and other graph databases/software, future entries should have in addition to text, exercises that users can perform with common software to reinforce their understanding of entries.