From entry classification in glossary Artificial Intelligence: humans at the heart of algorithms
A classification task or algorithm is one where the goal is to assign input data into one of two or more classes. In some cases, notably for supervised learning, these classes are preassigned by a human expert or other fixed system. In some forms of unsupervised learning classes may be inferred by the system using some form of clustering.
Used in Chap. 6: page 93