ICM stands for 'Internal Coordinates Mechanism' - a program designed by the head of the lab, Prof. Abagyan, in the early 80s. It was origifnally aimed at energy optimization of several biopolymers with respect to an arbitrary subset of internal coordinates such as bond lengths, bond angles torsion angles and phase angles.
The efficient and general global optimization method which evolved from the original ICM method is still the central piece of the program. It is this basic algorithm which is used for peptide prediction, homology modeling and loop simulations, flexible macromolecular docking and refinement.
However the complexity of problems related to structure prediction and analysis, as well as the desire for perfection, compactness and consistency, lead to the program's expansion into neighboring areas such as graphics, chemistry, sequence analysis and database searches, mathematics, statistics and plotting.
The original meaning became too narrow, but the name sounded good and was kept. The current integrated ICM shell contains hundreds of variables, functions, commands, database and web tools, novel algorithms for structure prediction and analysis into a powerful yet compact program which is still called ICM.
This is the same program used by several gigantic biotechnology enterprises, such as Novartis, Syrrx and Hitachi. It's also the core program that processes all the queries of the web-based server eBioinformatics.
To learn more about ICM, simply go to www.molsoft.com.