
People all over the world are discussing about 2012 end of Earth these days. Wherever you go it seems to be the hot topic.

Knowledge discovery and data mining (KDD) is an interdisciplinary area focusing upon methodologies for extracting useful knowledge from data. The ongoing rapid growth of online data due to the internet and the widespread use of databases have created an immense need for KDD methodologies. In this paper, We provide an overview of common knowledge discovery tasks and approaches to solve these tasks. The challenge of extracting knowledge from data draws upon research in statistics, databases, patte