What is the difference between Truetype, Typ-1 and Bitmap?
In the computers world co-exist basicaly 3 types of fonts: Bitmap, Truetype y Typ-1. Bitmap fonts represent the information of a letter in a bitmap of a few pixels. This type of fonts were very used in the 80's, however, actualy these fonts are in missuse.

TrueType and Typ-1 fonts doesn't require so many memory space as bitmap fonts, because these must to supply different bitmaps for the diversity of representation sizes. The letters of TrueType fonts are codified as scalable curves in the Postscript language and are recognized by the extension .ttf , while Typ-1 fonts require two archives of same name with the extension pfb and pfm . TrueType fonts were created for Apple-Macintosh, however, actualy are very used on the PC's. The archives of Apple fonts must to be processed with specialized programs like eg. Fontograbber for its use in computers with Windows operating system. Inversely, Apple cannot use directly PC fonts.

Hinting y Kerning
The width of well designed fonts vary, so the distance between the letters, opticaly, could be the same. This process its called Kerning and should be made manualy with different sizes of the font. Hinting is refered to the increment of the size of straight horizontal lines with very small font sizes. The other side, the straight horizontal lines are drawn smaller when the letter is represented in a big size.

Typographic Units: Point, Milimeter, Inch.
Commonly, the size of the fonts are expressed in points because its easier to talk about 11 points than 3,88 milimeters. The plomb letters were forming the base for the Didot Points, while TrueType and Typ-1 fonts make reference to the Pik Point. In graphics design programs or images manipulation, are being used as well milimeters, inches and pixels, and the units can be converted easily.

Article by Infomorelos.com
Traslation by Fontark.be