BIRCH

The Balance Iterative Reducing and Clustering using Hierarchies (BIRCH) algorithm is a Hierarchical Clustering Method suitable for large datasets of numeric data types(or data types which can be transformed to numeric data).

Instead of clustering data points, it creates small summaries of data which holds distribution information about data. other algorithms are often used in Birch generated data summaries.

Birch finds clusters without an initial number of clusters being set.