What is Mendalian inheritance and how does it work?

Mendelian Inheritance in Man (MIM) is a database that catalogs all the known diseases with a genetic component, and-when possible-links them to the relevant genes in the human genome. MIM is one of the databases housed in the U.S. National Center for Biotechnology Information (NCBI) and included in its search menus. It was started in the early 1960s and is available as a book currently in its 12th edition. The online version, OMIM, has been available since 1987, moved to the world wide web by NCBI in 1995, and in 2004 contained more than 15,000 records.

Source: Wikipedia