CID fonts create a practical approach to using a special font to reduce your PDF size and improve font rendering on your publications. The idea behind the concept is simple and easy to understand. They are fonts described as a character collection despite their glyphs not having names. A glyph indicator or CID identifies each member of a character collection, meaning CID numbers are used for different character collections. There are two PostScript resources needed for a CID font. A character map (CMap) is one, and it focuses on establishing the correspondence between glyphs and characters as executed by the PostScript show operator. It is a peculiar font encoding using CID instead of glyph names as its basis in most ways. CIDFont is the second requirement. It is somehow a Type 1 font that contains up to 65,536 glyphs indexed by CID numbers and not glyphs. The connection between CMap and CIDFont is established using the traditional findfont operator.