This font format is MicroStation-specific, and RSC fonts are stored in MicroStation resource (.rsc) files. A single resource file may contain several RSC fonts. RSC fonts have a number and a name, but only one font by a given number can be used at a time during a MicroStation session. If multiple RSC fonts share the same number, the last one to be loaded is the font assigned to that number in a given session. RSC fonts are locale-encoded, but support more than 255 characters (e.g. for some Asian languages). The code page of RSC fonts is specified in the font configuration file. If you use font characters for symbols, use RSC fonts rather than TrueType fonts.

MicroStation searches for RSC fonts in the RSC files found in MS_SYSFONTDIR and MS_FONTPATH, as well as any RSC file specified in MS_SYMBRSC. MicroStation does not search for RSC fonts in the directory of the requesting design file.

When exporting DGN files to DWG, MicroStation exports the required RSC fonts to the SHX format, generating SHX Unifonts by default (this can be overridden on a font-by-font basis in the font configuration file. This conversion works fairly well, except that SHX fonts do not support fill, so filled sections of RSC glyphs are drawn as outlines in SHX fonts.