A document is a written, drawn, presented, or memorialized representation of thought. The word originates from the Latin documentum, which denotes a "teaching" or "lesson": the verb doceo denotes "to teach". In the past, the word was usually used to denote a written proof useful as evidence of a truth or fact. In the computer age, "document" usually denotes a primarily textual computer file, including its structure and format, e.g. fonts, colors, and images. Contemporarily, "document" is not defined by its transmission medium, e.g., paper, given the existence of electronic documents. "Documentation" is distinct because it has more denotations than "document". Documents are also distinguished from "realia", which are three-dimensional objects that would otherwise satisfy the definition of "document" because they memorialize or represent thought; documents are considered more as 2 dimensional representations. While documents are able to have large varieties of customization, all documents are able to be shared freely, and have the right to do so, creativity can be represented by documents, also. History, events, examples, opinion, etc. all can be expressed in documents.
The page layout of a document is the manner in which information is graphically arranged in the space of the document, e.g., on a page. If the appearance of the document is of concern, page layout is generally the responsibility of a graphic designer. Typography concerns the design of letter and symbol forms and their physical arrangement in the document (see typesetting). Information design concerns the effective communication of information, especially in industrial documents and public signs. Simple textual documents may not require visual design and may be drafted only by an author, clerk, or transcriber. Forms may require a visual design for their initial fields, but not to complete the forms.
Documents in all forms frequently serve as material evidence in criminal and civil proceedings. The forensic analysis of such a document is within the scope of questioned document examination. For the purpose of cataloging and managing the large number of documents that may be produced during litigation, Bates numbering is often applied to all documents in the lawsuit so that each document has a unique, arbitrary, identification number.