The reading of typeset (or other to-be-disseminated) copy as a means of locating misspellings or other errors introduced during keyboarding.
"Proofreading" is not the same as "editing," yet in many smaller print and production companies without editors, these responsibilities tend to run together. In this context, proofreaders often look for what the author meant to say, editing grammatical errors as they come up, as opposed to correcting keyboarding errors exclusively. It is essential to clarify the client/customer's expectations in the production contract and to charge accordingly.