Defines a bookmark in the document.
A Bookmark exposes a document range with a name. A range can have zero length. The name should start with a letter, and must be unique in the collection of bookmarks in the current document. This collection is accessible with the SubDocument.Bookmarks property.
To create a new bookmark, use the BookmarkCollection.Create method. The BookmarkCollection.Select method is helpful if you want to select a bookmark. The BookmarkCollection.Remove method deletes the specified bookmark.