The term "autograph" comes from the Greek (auto = independent; graphein = writing). Thus "autograph" means those pieces of writing that an author has signed himself/herself; pieces of writing such as letters, cards, and documents thus are counted as autographs. Manuscripts (lat. manus = hand; scribere = writing) are always autographs.
One also speaks of an artist’s "autograph" when it is a question of his/her own markings or additions in a printed text or one that he/she did not write. Autographs have been collected since antiquity. Reasons for this can have to do with research or economic ambitions, for example when the autographs are of a famous or important person. The difference between an autograph and an autogram are that autographs impart a content and are thus considered historical documents.