1. A method for inserting and reusing document parts in an electronic document created within a word processing application program, comprising: receiving a selection of a document part category; displaying a gallery of document parts associated with the selected document part category, wherein the document parts include reusable portions of document content; receiving a selection of a document part from the gallery, wherein the document part includes a role identifier that indicates a role of the document part within the electronic document; identifying the role indicated by the role identifier; inserting the selected document part in the electronic document in accordance with the identified role; receiving user data; and modifying the selected part with the received user data, wherein modifying the selected document part with the received user data comprises adding additional data to the selected document part, the additional data comprising at least one document part from one or more alternative galleries of document parts and selecting an option from a menu comprising a plurality of options for modifying the selected document part, wherein selecting the option from the menu for modifying the selected document part comprises generating a submenu displaying thumbnails of additional document parts from the gallery and an option for removing a currently displayed document part, and wherein the submenu is utilized to replace a currently displayed document part with one of the additional document parts from the gallery without returning to the gallery.