Description of Entity Sets
Words: word stems that are used throughout all of the works that are cataloged in the database. It's a sort of lexicon containing every stem that the parser has ever come across.
WordContexts: the full word that a particular instance of a stem corresponds to. Includes any punctuation/whitespace surrounding the word used.
Criticism: online literary criticism of a particular work. Contains metadata for the criticism as well as the URL where the criticism may be found.
Author: information about authors.
Period: information about the various regions and eras used to classify works, such as "19th Century American"
Works: information about works (books, collections, etc.) in the database.
Pages: data on individual pages in a work. This is a weak entity set because the key here is the page number, so a work is required for uniqueness.