FOCAL is an interpreted programming language resembling JOSS. The name is an acronym for Formulating On-Line Calculations in Algebraic Language.Largely the creation of Richard Merrill, FOCAL was initially written for and had its largest impact on the Digital Equipment Corporation's (DEC's) PDP-8 computers. Merrill wrote the original (1968) and classic FOCAL-69 interpreters for the PDP-8.