Category, plural categories, may refer to:

General uses

Classification Classification is the activity of assigning objects to some pre-existing classes or categories. This is distinct from the task of establishing the classes themselves (for example through cluster analysis). Examples include diagnostic tests, identif ...

, the general act of allocating things to classes/categories

Philosophy

* Category of being * ''Categories'' (Aristotle) * Category (Kant) * Categories (Peirce) * Category (Vaisheshika) * Stoic categories * Category mistake

Science

Cognitive categorization Categorization is a type of cognition involving conceptual differentiation between characteristics of conscious experience, such as objects, events, or ideas. It involves the abstraction and differentiation of aspects of experience by sorting ...

, categories in cognitive science *

Statistical classification When classification is performed by a computer, statistical methods are normally used to develop the algorithm. Often, the individual observations are analyzed into a set of quantifiable properties, known variously as explanatory variables or ''f ...

, statistical methods used to effect classification/categorization

Mathematics

Category (mathematics) In mathematics, a category (sometimes called an abstract category to distinguish it from a concrete category) is a collection of "objects" that are linked by "arrows". A category has two basic properties: the ability to compose the arrows asso ...

, a structure consisting of objects and arrows * Category (topology), in the context of Baire spaces * Lusternik–Schnirelmann category, sometimes called ''LS-category'' or simply ''category'' * Categorical data, in statistics

Linguistics

* Lexical category, a part of speech such as ''noun'', ''preposition'', etc. *

Syntactic category A syntactic category is a syntactic unit that theories of syntax assume. Word classes, largely corresponding to traditional parts of speech (e.g. noun, verb, preposition, etc.), are syntactic categories. In phrase structure grammars, the ''phrasa ...

, a similar concept which can also include phrasal categories * Grammatical category, a grammatical feature such as ''tense'', ''gender'', etc.

Other

Category (chess tournament) A chess tournament is a series of chess games played competitively to determine a winning individual or team. Since the first international chess tournament in London 1851 chess tournament, London, 1851, chess tournaments have become the standard ...

* Objective-C categories, a computer programming concept * Pregnancy category * Prisoner security categories in the United Kingdom *

Weight class (boxing) In boxing, a weight class is a measurement Human weight, weight range for boxers. The lower limit of a weight class is equal to the upper weight limit of the class below it. The top class, with no upper limit, is called heavyweight in professi ...

List of software categories Software categories are groups of software. They allow software to be understood in terms of those categories, instead of the particularities of each package. Different classification schemes consider different aspects of software. Categorization ...

Categories (word game) Categories is a word game where players attempt to list words that fit into particular categories, all starting with the same letter. Players start by deciding on a list of categories between them, such as "town" or "actor", and each writing that ...

, a classic party game * Saffir–Simpson hurricane wind scale, a common categorization of hurricane intensities *

Categories of New Testament manuscripts New Testament manuscripts in Greek can be categorized into five theoretical groups, according to a schema introduced in 1981 by Kurt and Barbara Aland in ''The Text of the New Testament''. The categories are based on how each manuscript relat ...

* Network cable categories: 1, 2, 3, 4, 5/5e, 6/6a, 7/7a (F) * A classification in a system of