Data mining (also known as Knowledge Discovery in Databases - KDD) has been defined as "The nontrivial extraction of implicit, previously unknown, and potentially useful information from data"[1]

It uses machine learning, statistical and visualization techniques to discovery and present knowledge in a form which is easily comprehensible to humans.

[1] W. Frawley and G. Piatetsky-Shapiro and C. Matheus, Knowledge Discovery in Databases: An Overview. AI Magazine, Fall 1992, pgs 213-228.

See Also: Introduction To Data Mining