CRISTAL System Macros: A macro command language is the heart of the application development capabilities of the CRISTAL System described in Section 4.2.5 and in Appendix 1 (Appdcris). In CRISTAL, the application developer uses macros to create the program structure necessary to accommodate specific information management needs. CRISTAL macro statements can initiate an automated sequence of actions or program functions, such as incremental movement through a block of worksheet cells to facilitate data entry or to validate data type. Macro statements can prompt the application user for passwords or data input, and retrieve program data from inactive files stored in disk memory. CRISTAL macro routines can also activate the display of images, graphs, or worksheets in an integrated information retrieval system or an interactive instructional program. An application developer with a good understanding of the CRISTAL macro language can assemble appropriately tailored programs for a user base possessing varied levels of computer and professional skills. These application users would only require operational knowledge of the specific application interface, and could become skillful system operators without possessing any understanding of the CRISTAL program itself. As the application developer becomes more familiar with the structure, utility, and application of the CRISTAL macro command set, complex command sequences and routines can be used to assemble the comprehensive structure for a tailored program application. Authoring Systems Using Macro Commands CRISTAL Data Links