The two books are related to each other in that Shore used Szarkowski's book to teach a class at Bard College. His book developed from this class.
You will get a good overall introduction to photography through these two books and the bbc series 'The Genius of Photography'. This is available online and in the library (with accompanying book). Watch Episode 2 - Documents for Artists before next week's session.
Below is a the seminar outline for this semester. This may change as we progress, but touches on the basic themes and reading material.