Choosing a Unit Display Mode

Unit display mode options select perceived scale of the model and the precision displayed in the status bar.  For example to scale a model using 1/1000th of an inch choose File: Unit Display Mode: 0.001 menu option.  To scale using 1/10th of a millimeter choose 0.01 option, this can be interpreted as cm.mm where whole part is cm and the factional part is mm.  The other consideration when choosing is texture resolution, higher resolution textures use a larger geometric scale and a smaller unit display mode makes the scale appear relative, although is not required to be set. 

Note: Create new object, Multi-Paste, Rotate/Translate/Scale dialog units are relative to current Unit Display Mode setting, all other dialog settings are in absolute units.