What is GLM? It's software that you install on your computer that tells you whether or not your boat meets stability standards. GLM stands for GHS Load Monitor. GHS (General HydroStatics) is the software used by many naval architects for their stability calculations. GLM is actually a special version of GHS optimized for use by vessel operators. If you have a trim and stability book, GLM is the "electronic" version of it.

The big difference is that GLM is quick and easy to use with any loading condition while the T&S book shows only a few sample conditions and requires that you do dome additional calculations by hand or some other means to get an accurate stability assessment of other conditions.