Consult specialized encyclopedias or dictionaries to get a broad overview of a subject, a concise overview of a concept, school of thought or person'
Dictionaries provide short definitions (a sentence or two, or a short paragraph) of terms or a brief overview of an subject, etc.
Encyclopedias contain longer essays that provide a more in-depth discussion of topics.
To find encyclopedias or dictionaries on your topic, search Omni using the keywords of your topic combined with "encyclopedia" or "dictionaries" or look for these words following a subject heading.