AMBER (an acronym for Assisted Model Building with Energy Refinement)'s a family of force fields for molecular dynamics of biomolecules originally developed by the late Peter Kollman's group at the University of California, San Francisco. AMBER's also the name for the molecular dynamics simulation package that implements these force fields. It's maintained by an active collaboration between David Case at Rutgers University, Tom Cheatham at the University of Utah, Tom Darden at NIEHS, Ken Merz a… (More on Amber)