Cloud computing Technology changing rapidly and is forming a layer that is touching each and every aspect of life like power grids, traffic control, medical and health care, water supply, food and energy library science is not exception to it. Information technology impacted positively on library and information system and services they provide for users. The libraries have been automated, networked and now moving towards manual libraries to paper less or virtual libraries. To gather challenges in the profession librarians are also applying different platforms in Library science filed for attaining economy in information handling. This paper overviews the basic concept of newly develop area known as cloud computing. The use of cloud computing in libraries and how cloud computing actually works is illustrated in this communication.