Acronym for source lines of code. A metric that is a count of the number of lines of source-language statements of a software module, package, or complete software system. There is no defined standard for determining which lines should be counted. Most organizations will exclude blank lines and include lines containing executable statements, but differ on whether to include comment lines and data-definition lines. Many software cost-estimation approaches are based on estimating the number of SLOC in a proposed project (see COCOMO).