OpenType
Basic information about OpenType fonts:
• Works on both Macintosh and PC computers.
• One file per font only. Makes it easy to handle.
• Supports multiple languages in a single font.
• Can contain typographic features (OpenType features) such as small caps, old style figures, tabular figures, swashes, stylistic alternates, superiors, fractions, ligatures and much more.
• Basically no limits when creating them. OpenType fonts can contain 64.000 glyphs in a single font, which makes them very flexible. Symbols, logotypes and other vector graphics can be built in the fonts for easy access.

Read more about OpenType at Adobe or MyFonts