Criticism is the construction of a judgement about the negative qualities of someone or something. Criticism can range from impromptu comments to a written detailed response. Criticism falls into several overlapping types including "theoretical, practical, impressionistic, affective, prescriptive, or descriptive".

Criticism may also refer to an expression of disapproval of someone or something. When criticism of this nature is constructive it can make an individual aware of gaps in their understanding and it can provide distinct routes for improvement. Research supports the notion that using feedback and constructive criticism in the learning process is very influential.

Critique vs. criticism: In French, German, or Italian, no distinction is drawn between 'critique' and 'criticism'. The two words both translate as critique, Kritik, and critica, respectively. In the English language, philosopher Gianni Vattimo suggests that criticism is used more frequently to denote literary criticism or art criticism while critique refers to more general and profound writing as Kant's Critique of Pure Reason. Another distinction that is sometimes made is that critique is never personalized nor ad hominem and is presented in a way that encourages rebuttal or expansion of the ideas expressed. Nonetheless, the distinctions are subtle and ambiguous at best.

The term "brickbat" is sometimes used to mean "an unfavourable criticism, unkind remark or sharp put-down". The term originated in the 17th century, derived from the practice of throwing bricks as projectiles at a person who was disapproved of.

In some contexts, such as literary criticism and art criticism, the word criticism is used as a neutral word that is synonymous with evaluation.