The software provides a flexible environment to display, manipulate, and analyze small and large molecules, proteins, nucleic acids, and their interactions.
[2] Most of its development occurred during 1989–2000 at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany.
[3] In 2000, maintenance of the software moved to the Dutch Center for Molecular and Biomolecular Informatics (CMBI) in Nijmegen, Netherlands.
WHAT IF provides a flexible environment to display, manipulate, and analyze small molecules, proteins, nucleic acids, and their interactions.
One notable use was detecting many millions of errors (often small, but sometimes catastrophic) in Protein Data Bank (PDB) files.