Page layout is the process by which the elements are laid on the page orderly, aesthetically, and precisely. Main types of components to be laid out on a page include text, linked images that can only be modified as an external source, and embedded images that may be modified with the layout application software. Some embedded images are rendered in the application software, while others can be placed from an external source image file. Text may be keyed into the layout, placed, or (with database publishing applications) linked to an external source of text which allows multiple editors to develop a document at the same time.