Set theory: Meaning (information, definition, explanation, facts)

Set theory is the mathematical theory of sets, which represent collections of abstract objects. It has a central role in modern mathematical theory, providing the basic language in which most of mathematics is expressed.

For more information on set theory in Wikipedia, see:

• Naive set theory is the original set theory developed by mathematicians at the end of the 19th century
• Axiomatic set theory is a rigorous axiomatic theory developed in response to the discovery of serious flaws (such as Russell's Paradox) in naive set theory.
• Various versions of logic have associated sorts of sets (such as fuzzy sets in fuzzy logic).
• Internal set theory an extension of axiomatic set theory that admits infinitesimal and illimited non-standard numbers.
• Musical set theory may be considered the application of mathematical set theory to music.