Like line-oriented diff , finding changes is a heuristic process which can become confused, particularly when a document is reorganised, moving large sections around. Still, despite its shortcomings, many source code control systems have been built upon diff , and a word diff may prove adequate for many cases of document revisions. These tags, not being valid HTML tags, would be ignored by browsers, allowing the author to preview the document as it was edited. This approach has the disadvantage that new back links added to the document during the editing process will be lost. The file consists of various control records, each identified by an asterisk in the first column.
All control records are case-insensitive.
The line is a comment and is ignored. The text is displayed in the confirmation box returned to a user who attempts to add a back link. For example, the message might notify the sender that the document has been superseded by a new edition, or invite the person who made the link to E-mail the author with a description of it. The addition of new back links is disabled. Existing back links can still be followed.