Tracking is a term used in typography to refer to the spacing between characters in a range of letters. It is also known as letter-spacing. Tracking adjusts the letter-spacing uniformly over a range of characters, affecting the visual density of a word, phrase, or paragraph. It can be used to decrease or increase the horizontal spacing between a range of letters or characters. Tracking can be applied to all of the text in a project at once, and it can also change line endings and reduce the length of full lines of text. Selective tracking can also squeeze additional characters into a line to help save space. Tracking is measured in 1/1000 em, a unit of measure that is relative to the current type size.

Designers use tracking for two main reasons: to improve the look of typeset text and to improve the overall legibility of a project. Increasing or decreasing tracking has the power to reduce the amount of hyphenation in a paragraph, and banish widows and orphans. Widows are lone words at the end of a paragraph, while orphans are lone words at the top of a page that should belong on the previous page.

Tracking is a single part of a full strategy to improve the appearance of a page or a small piece of text. It doesnt replace things like kerning and leading for good copy fitting. When increasing or decreasing tracking in a paragraph, its important to consider the font being used, as each typeface is different. There are no definitive values for tracking adjustments, and its an aesthetic judgment call. Its overdone when a block of text looks like a painful dense black blob or a wispy gray cloud.

In summary, tracking is a term used in typography to refer to the spacing between characters in a range of letters. It can be used to decrease or increase the horizontal spacing between a range of letters or characters, and it affects the visual density of a word, phrase, or paragraph. Designers use tracking to improve the look of typeset text and to improve the overall legibility of a project. When increasing or decreasing tracking in a paragraph, its important to consider the font being used, and its an aesthetic judgment call.