Another source of information that you will be expected to use are articles. Magazine and newspaper articles are written for the general public and go through a general editorial process.
Journal articles are usually focused on very specific issues and are written for researchers and students studying the field. Books focus on specific topics as well, but journal articles usually go deeper. For example, a book may focus on the civil rights movement and its influence on education, however a journal article may examine a specific school district or geographic location in relation to the civil rights movement.
Another difference between articles and books is that articles, with the exception of historically focused articles, present more current information. It takes time, sometimes years, to write, edit, and publish a book. While it also takes time to write, edit, and publish articles, they are usually published more quickly.