Plasmid map generation is one of the oldest and most frequently performed operations in bioinformatics. Indeed, probably almost every practicing molecular biologist has worked with or generated a plasmid map to guide them through the cloning or plasmid manipulation process. Because of the size and complexity of plasmid molecules, computer-generated maps are absolutely essential to identify, locate & analyze key regions in a vector sequence. As early as the 1980s standalone computer programs were being described that supported the presentation and manipulation of plasmid maps on specific platforms & computer operating systems. Many of these early freeware packages have since been replaced by more sophisticated and far more user-friendly commercial packages, such as SimVector (Premier BioSoft), GeneTool (BioTools), VectorNTI (Informax, Invitrogen), MacVector (Accelrys), DNA Strider & LaserGene (DNAStar). Currently there are remarkably few freeware plasmid mapping programs still available, although pDRAW32 (AcaClone) is one example of an installable standalone package that supports plasmid mapping.