Sets are collections of items that are grouped together based on a common characteristic or property. In mathematics, a set is a well-defined collection of distinct objects, considered as an object in its own right. Sets can be finite or infinite, and can contain any type of element, such as numbers, symbols, or other sets. Sets are used in a variety of mathematical concepts, including functions, relations, and probability. They are essential for organizing and categorizing information, and are a fundamental concept in set theory. Understanding sets is crucial for various branches of mathematics and is key to solving complex problems in the field.