Gnuplot is a portable command-line driven interactive datafile (text or binary) and function plotting utility for UNIX, IBM OS/2, MS Windows, DOS, Apple Macintosh, VMS, Atari and many other platforms.
It was originally intended as graphical program which would allow scientists and students to visualize mathematical functions and data.
It does this job pretty well, and in addition it serves as non-interactive plotting engine for miscellaneous portable third-party applications, like Octave.
Gnuplot is developed and supported since 1986, and having its scripts and commands easy to understand text files, it is time-portable as well.
