MBCS font is a font which provides both SBCS and DBCS fonts. In the fsType of the FONTMETRICS or the FATTRS structure, you will find the value like FATTR_TYPE_SBCS, FM_TYPE_DBCS, FATTR_TYPE_MBCS or FM_TYPE_MBCS. The value implies the font is an SBCS, DBCS or MBCS font.
SBCS fonts provide font data of SBCS character set only and DBCS fonts provide font data of DBCS character sets only. The MBCS fonts provide the font data for both SBCS and DBCS character set. In DBCS PM, both SBCS fonts and MBCS fonts are supported. SBCS fonts are the same fonts that are supported in SBCS OS/2, so application can use all the APIs to handle the SBCS fonts like in SBCS OS/2. In DBCS PM, there are MBCS raster fonts and MBCS outline fonts.