Now-a-days every organization is moving towards on web based application and cope up lots of data sets. Data may be structured, unstructured or semi-structure. These data need processing, analysis and storage in proper format using innovative techniques and methodologies. Big data parameterized into three basic categories Volume, Variety and Velocity. The social media like Facebook, Whatsapp, Twitter, hike. are generating lots of data in a day in the form of textmessages, audio-recording, images, videos etc. The problem which appears is how to manage this huge data in a systematic way because users want quick response on web search or on smart phone access using web apps. In this paper we have studied how big data invoke in different areas like social media, atmosphere, hospitals, research centers etc. We have suggested contributions in big data categories, applications in different area's like in Machine learning, Social Network, Bio-Informatics, Data Mining, and Clouds along with challenges, future scope and storage prospects.