The H-Index, devised by Jorge Hirsch in 2005, a physicist at the University of California, is a numerical measure to know the productivity and influence of a researcher.
For example, a scholar with an H-index of 6 had published 6 papers, each of which has been cited by other people at least 6 times.
The h-index is defined as the maximum value of h such that the given author/journal has published h papers that have each been cited at least h times. The index works properly only for comparing scientists working in the same field; conventions for citation differ widely among different fields.
