Join

Join may refer to:


 * Join (law), to include additional counts or additional defendants on an indictment
 * In mathematics:
 * Join (mathematics), a least upper bound of sets orders in lattice theory
 * Join (topology), an operation combining two topological spaces
 * Join (sigma algebra), a refinement of sigma algebras
 * Join (algebraic geometry), a union of lines between two varieties
 * In computing:
 * Join (relational algebra), a binary operation on tuples corresponding to the relation join of SQL
 * Join (SQL), relational join, a binary operation on SQL and relational database tables
 * join (Unix), a Unix command similar to relational join
 * Join-calculus, a process calculus developed at INRIA for the design of distributed programming languages
 * Join-pattern, generalization of Join-calculus
 * Joins (concurrency library), a concurrent computing API from Microsoft Research
 * Join Network Studio of NENU, a non-profit organization of Northeast Normal University
 * Joins.com, the website for South Korean newspaper JoongAng Ilbo
 * Joining (woodworking), woodworking processes of combining two or more pieces of wood together, generally through the use of nails or screws
 * Joining (metalworking), metalworking processes which combine two or more pieces of metal together, typically by the use of screws or welding