The adjustment of space between pairs of letters to make them more visually appealing is known as kerning. It is normally applied to individual letter pairs in headlines or other large type. Kerning is not usually done with body text because the gaps between characters at body text sizes is generally not as distracting.
Both kerning and tracking are types of letterspacing or character spacing but kerning is applied selectively to just a few specific pairs of letters. Adjustment of spacing in body text or for more than just a few letters is done with tracking.
Some typefaces come with kerning pairs — commonly kerned pairs of letters with the kerning (spacing between letters) already adjusted. The kerning options in some desktop publishing software can access these kerning pairs. Additionally, some apps allow the user to edit the kerning tables to add their own kerning pairs that may not already exist for that font or adjust the spacing between existing kerning pairs.
"Anywhere from 50 to 1000 or more kerning pairs may be defined for any one font. A handful of the thousands of possible kerning pairs: Ay AW F, KO wa — Kerning and Tracking Overview
- Use caution when kerning headlines that make use of ligatures. These double or triple letter sequences are all one character and can't be kerned as individual letters and depending on the level of kerning used in other characters in the same headline, spacing could become visually awkward.
- Use extreme kerning or over-kerning to create tightly spaced or overlapping characters, perhaps for a newsletter nameplate or as part of a logo.
- Editing the kerning tables (in software that offers that feature) frees you from repeatedly kerning the same groups of letters in a font when they appear multiple times in a publication such as a brochure or newsletter.
- Text set in ALL CAPS will almost always need some kerning.