I. Introduction
This In many applications, Data is growing fastly day by day and there are massive data collections in the systems. For finding important information from these massive data required methods or techniques of data mining.so we can say that knowledge extraction become important task now a days. In recent trends, most of applications like Health care, medical analysis [1] [11], weather and climate prediction, network intrusion detection [3], automatic text data analysis and categorization [4], finance and market prediction, multimedia data analysis etc. having large amount of data. Manually analysis and information extraction from this large amount of data, is not an easy task for human in short amount of time with accuracy. Therefore, to avoid this problem, most of people or organizations are depend on different techniques of data mining. In next section, we see some data mining methods overview like clustering, classification and prediction [1] and its behavior. This paper discusses k-Nearest Neighbor classifier in the next section.