RbApp is a collection of reusable REALbasic classes to help programmers create industrial strength applications on Macintosh and Windows. The main components are RbEdit (Large Plain Text Editing with Undo/Redo, Find/Replace, etc), RbView (Page Layout), RbCommand (Undo/Redo commands), RbPalette (Toolbars & Palettes), RbStringList, RbXML (Easy XML Read/Write), RbHelp (Interactive Application Help) and RbLibrary (Reusable Methods and Classes).