Wolfram Research
Wolfram Math World: Sets
This page discusses sets and set theory in mathematics and probability, and it discusses the notation and properties of sets.
Other
Earlham College: A Crash Course in Infinite Sets
This site aims to provide all essential information on infinite sets in a way the reader will immediately understand.
Oswego City School District
Regents Exam Prep Center: Set Builder and Interval Notation
Use this lesson, practice exercise, and teacher resource when planning instruction on sets and interval notation. Offers simple definitions and examples, an eleven-question online quiz, and a .pdf worksheet for students to complete while...
Houghton Mifflin Harcourt
Holt, Rinehart and Winston: Homework Help Independent Practice: Sets
Get independent practice working with sets. Each incorrect response gets a text box explanation and another try. Correct responses are confirmed.
Other
Stat Soft: Statistics Glossary
Dozens of statistical terms are defined and illustrated in this glossary.
University of St. Andrews (UK)
University of St. Andrews: History of Set Theory
This page, which is provided for by the University of St. Andrews, traces the history of Set Theory as well as the concept of infinity and the infinite set.
Other
Jeff Miller: Uses of Symbols of Set Theory and Logic
This fun personal page offers the history of various symbols in set notation. (The bibliography link is located at the bottom of the page.)