Typographical error

A typographical error (often shortened to typo), also called misprint, is a mistake made in the typing process (such as a spelling mistake) of printed material. Historically, this referred to mistakes in manual type-setting (typography). The term includes errors due to mechanical failure or slips of the hand or finger, but excludes errors of ignorance, such as spelling errors, or the flip-flopping of words such as "then" and "than". Before the arrival of printing, the "copyist's mistake" or "scribal error" was the equivalent for manuscripts. Most typos involve simple duplication, omission, transposition, or substitution of a small number of characters.

Fat finger, or "fat-finger syndrome", a slang term, refers to an unwanted secondary action when typing. When one's finger is bigger than the touch zone, there can be inaccuracy in the fine motor movements and accidents occur. This is common with touchscreens. One may hit two adjacent keys on the keyboard in a single keystroke. An example is buckled instead of bucked, due to the L key being next to the K key on many keyboards.

Certain typos, or kinds of typos, have achieved widespread notoriety and are occasionally used deliberately for humorous purposes. For instance, the British newspaper The Guardian is sometimes referred to as The Grauniad due to its reputation for frequent typesetting errors in the era before computer typesetting. This usage began as a running joke in the satirical magazine Private Eye. The magazine continues to refer to The Guardian by this name to this day.

Typos are common on the internet in chatrooms, Usenet, and the World Wide Web, and some—such as "teh", "pwned", and "zomg"—have become in-jokes among Internet groups and subcultures. Pr0n is not a typo but an example of obfuscation.

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