Questions relating to maneuvers that take advantage of short-term opportunities, such as forks, discovered attacks, skewers, etc.
Tactics are the concrete maneuvers (e.g. forking two pieces with a knight, pinning a piece to the opponent's king, or unleashing a discovered check) that chess players use and combine in order to achieve their overall goals in a game. They are the building blocks which underlie successful strategies.
Tactics represent the raw calculation side of chess, rather than the speculative, intuitive aspects of the game. That is, perhaps, unless you're Mikhail Tal, former world champion and so-called "Magician from Riga".