Bookmarks

While reading a book you may wish to mark some pages so they can be easily reviewed later. Only a few pages can be marked before the whole book becomes a mess. Also, with books from a library one is normally not allowed to add bookmarks (in a destructive way).

In a hyperdocument the equivalent of a page is a node. A hypertext system lets you mark nodes, by putting a name in a list of bookmarks. This name can be a system-defined name or a name you can choose. Most hypertext systems do not display the list of bookmarks unless you ask for it, so the bookmarks do not hinder the reading process.

The ability to add a bookmark and to jump to the indicated node at any time can also be viewed as adding links from every node to the "bookmark node", and from the bookmark node to the nodes to which it contains a reference. Many hypertext systems store bookmarks in a special file or database, with a proprietary format. The user-interface then simply provides a facility which feels like following links. Recent browsers for World Wide Web save bookmarks as an HTML file, so that the bookmark node can be used like an ordinary node in the hyperdocument.