Copy-editing consists in the process of checking, cleaning and improvement of the text, so that it is clear and easily comprehensible, it is precise (expresses its ideas correctly), coherent (in regard to discourse development) and consistent (editorial decisions are applied uniformly throughout the text).
To achieve this, the editor has to eliminate all grammar, spelling and typographical errors, must give the text unity and consistency in all aspects, with an adequate and correct use of the language. This includes syntax, spelling, semantics, lexical or eidetic repetitions, unnecessary redundancies, vagueness, and contradictions, use of capital letters, punctuation mechanics, incorrect homonyms and printing errors.
The copy editor must make sure that the style of the text suits the general use of the language, but must also take into account the appropriate stylistic devices for the audience of the book, such as the area, the subject or the genre of the work. Therefore, he will pursue an adequate form for the communication requirements of the environment in which the text is used, without affecting previous corrections or stylistic devices characteristic for the author – a comprehensible distinctive personal stamp – as long as they are grammatically correct.