The purpose data mining is to extract the useful information from a bulky data set. Clustering analysis is an important technique in the field of data mining. It is the process of grouping similar vectors of a document into number of clusters. The basic procedure for clustering is to divide document into set of terms and assigns weight to these terms and classify them according to their features and weights assigned to them with the help of algorithm. In this paper, the authors are discussing various proposed clustering methods. Clustering analysis is unsupervised learning as different documents have different features and the documents are classified according to them.