Ligature

In typesetting, some letter combinations are printed as a single unit instead of two different letters with a space between. This is for aesthetic reasons usually. The pairs most often combined include: fi, ff, fl, ffi, ffl, and the dipthongs ae and oe. Some fonts actually include some of the ligatures as characters within the font. If not, kerning can be used to bring the letters together in most word processing and page layout programs.

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