Octave is a free computer program for performing numerical computations, which is mostly compatible with MATLAB. It is part of the GNU project.
The project conceived around 1988. At first it was intended to be a companion to a chemical reactor design course. Real development only started by John W. Eaton in 1992. The first alpha release dates back to January 4, 1993 and on February 17, 1994 version 1.0 was released.
The name has nothing to do with music. It was the name of a former professor of one of the authors of Octave who was known for his ability to quickly come up with good approximations to numerical problems.