CERN is the European Organization for Nuclear Research and it stands for Conseil Européen pour la Recherche Nucleaire. It was established on 29 September 1954 in Geneva, Switzerland and its purpose is to operate world’s largest particle based laboratory. In this laboratory, they study about the basic constituents of matter with the help of “The Large Hadron Collider” (world’s most complicated scientific instrument). It has more than 3,900 employees which include 2400 full time and 1500 part time employees.
To know more about CERN, read from this link : http://en.wikipedia.org/wiki/CERN