While almanacs are best used to answer simple questions of current or historical fact, the variety and diversity of information they contain is indeed wondrous. They tend to focus on information that changes and must be brought up to date. No two almanacs contain exactly the same material, so it is often necessary to use more than one. Information can be located by looking up the subject in the index. The index may be at the back, in front, or even in the middle.
Atlases are collection of maps or charts bound in a volume.
It may cover the entire world or specific regions and frequently contains indexes of place-names, populations, natural resources, main industries, and other factual information. Atlases may include population charts, air distance tables, economic and political distribution maps, etc. They also contain brief notes indicating the subject treated or comments on the usefulness of a book. Bibliographies that are located at the end of a chapter or book are good starting points for further research. Biographies provide information about a person's life and works.