Proof reader

Proof-reading traditionally means reading a proof copy of a text in order to detect and correct any errors. Modern proofreading often requires reading copy at earlier stages as well. A proof copy is a version of a manuscript that has been typeset after copy-editing. Proof typescripts often contain typographical errors introduced by mistyping (hence the word typo to refer to misplaced, missing or incorrect characters). Traditionally, a proofreader checks the typeset copy and marks any errors using standard proof correction marks (such as those specified in style manuals, by house style, or, more broadly, by the international standard.

The term proofreading is sometimes used incorrectly to refer to copy-editing. This is a separate activity, although there is some overlap between the two. Proofreading consists of reviewing any text, either hard copy on paper or electronic copy on a computer, and checking for typos and formatting errors. This may be done either against an original document or "blind" (without checking against any other source). Many modern proofreaders are also required to take on some light copy-editing duties, such as checking for grammar and consistency issues.

A typographical error (shortened as typo) is a mistake made during, originally, the manual type-setting (typography) of printed material, or more recently, the typing process. The term includes errors due to mechanical failure or slips of the hand or finger, but excludes errors of ignorance. Before the arrival of printing, the "copyist's mistake" was the equivalent for manuscripts. Most typos involve simple duplication, omission, transposition, or substitution of a small number of characters.

Though the term "typo" excludes errors of ignorance, it is common to find it used as a euphemism to describe instances of poor spelling, punctuation, or grammar, such as accidentally typing a homophone.When using a typewriter without correction tape, typos are commonly overstruck with another character such as a slash. This saves the typist the trouble of retyping the entire page to eliminate the error, but as evidence of the typo remains, it is not aesthetically pleasing. In instant messaging, users often send messages in haste and only afterwards notice the typo. It is common practice to correct the typo by sending a subsequent message where an asterisk precedes or follows the correct word.