What is cluster analysis?

Cluster analysis, also known as clustering, is a data analysis technique used to group a set of objects in such a way that objects in the same group (called a cluster) are more similar to each other than to those in other groups (clusters). It is a main task of exploratory data mining, and a common technique for statistical data analysis used in many fields, including pattern recognition, image analysis, information retrieval, bioinformatics, data compression, and computer graphics. Common uses include customer segmentation, anomaly detection, and data summarization.