Morphological information is useful for parsing, lemmatization, and in several natural language applications: text generation, machine translation, document retrieval, etc. In this paper, we shall be less concerned with what morphological processing systems are like (cf. Sproat 1992) than with the applications of computational morphology. We first present the kind of morphological information used by NLP (natural language processing) systems. That information is inflectional or derivational and may be encoded in lexical databases or retrieved dynamically through simple processing. The best known computational systems are presented, including some new methods to automatically acquire morphological information. Secondly, several technological applications using morphological information are described. In these sections, we have chosen to favor the description of some representative works in the corresponding fields, so as to illustrate how morphology is involved; we do not lay claim to exhaustiveness. This review aims at showing how truly useful morphology is for NLP systems.