The MWAPI specification defines twenty-one event type keywords for indicating events that can cause callback processing to occur for gadgets. The MWAPI specification makes allowances for implementers to specify event types, but implementation values are not guaranteed the portability of standard values. The character "Z" is reserved for the first character in an implementation keyword. The gadget type determines the event types it can use and respond to. Table 5.9 lists the event type keywords available for gadgets. Event type keywords are uppercase keywords that must be enclosed in quotes or assigned as a variable. Table 5.10 identifies the event type keywords to the gadgets that can receive events.

The keywords can be divided into three categories. The descriptions are discussed from the point of view of the applications user. All events listed can be triggered by an application.