pattern matching

from the GNU version of the Collaborative International Dictionary of English.

• noun (Computers) A technique in automated data analysis, usually performed on a computer, by which a group of characteristic properties of an unknown object is compared with the comparable groups of characteristics of a set of known objects, to discover the idenity or proper classification of the unknown object.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun computer science the act of checking some sequence of tokens for the presence of the constituents of a pattern