Bio informatics is a biological study that uses computer programming to process biological data. Bio informatics makes use of data mining techniques to study protein complexes, metabolic pathways and gene networks. At present Protein Protein interaction network (PPI) is one of the key topic for the development and progress of modern system biology. The objective behind this presentation explores bioinformatics basis, computational usage in bioinformatics, interaction patterns of proteins which include prediction and analysis of PPI networks. It also covers existing methods, tools, databases utilized in building proein protein interaction networks.