Instruments are classified according to their process function and instrument type. Every instrument that you create in Smart Instrumentation has a process function and must be assigned to an instrument type. Examples of process functions are level, pressure, temperature, control valve, relief valve, and so forth. There is also a process function named General which is used for instruments that are not intended for one particular process. Instruments of a particular type usually have predefined properties or items, which you specify in the instrument type profile; for example, you can specify that when creating any instrument of a particular type, the software also creates a specification sheet, a device panel, and a cable. In the definitions used in this Tutorial, the instrument type also comprises part of the tag naming convention.