High Quality Content by WIKIPEDIA articles! OpenGrok is a source code search and cross reference engine. It helps you search, cross-reference and navigate your source tree. It can understand various program file formats and version control histories like Monotone, SCCS, RCS, CVS, Subversion, Mercurial, Git and Bazaar. In other words it lets you grok (profoundly understand) the open source, hence the name OpenGrok.