The Open Access (OA) movement started in 1960s and gained momentum in the 1990s with the advent of Internet and digital archiving. The world famous physicist Leó Szilárd was one of the first supporters of the basic principle of OA. It is said that in the 1940s itself he suggested that at the beginning of the career each scientist should be issued with 100 vouchers to pay for his papers. Szilard's light comment was indeed to become a reality much later. It is now possible to publish a scholarly article and also make it instantly accessible anywhere in the world through computers and internet connection or any other digital data access system. The social movement towards Open Access is mainly carried out by academia, dedicated to the principle of open access to information without any financial barrier to the reader/user, especially for communities of the developing and under-developed countries. This movement slowly became the subject of much discussion among researchers, academics, librarians, university administrators, funding agencies, government officials, commercial publishers and learned-society publishers. In the sections that follow major worldwide OA projects, databases, initiatives and networks are highlighted.