Guitar is a very specific, free software to calculate so called guitar gears. A guitar is a program used to find a set of 4 gears, forming a transmission (so called a guitar) with a given gear ratio, used in machines for processing teeth, threads, etc. It is a program used to find a set of 4 gears.

Replaces books such as "40,000 gears" and has no typical limitations (ranges, accuracy, errors). The program is self-documentation and contains two language versions - Polish and English.