Event structures can be used to react to user interaction with your VI. They execute code you create when certain events you select occur. These events can range from a mouse click on a front panel control, an indicator's value changing, or even someone trying to close your VI.
In this snippet there are four front panel controls with different symbols on them. Clicking on any of these symbols, while the VI is running, will cause the selected symbol to be displayed using an array of LED indicators. As an added bonus, you can also clear the display of the current symbol by putting your cursor on top of the array of LEDs and scrolling your mouse wheel in either direction.
If you would like to add more events to this example you can right click on the event structure on the block diagram and select "Add Event Case..." If you wish to delete events you simply select "Edit Events Handled by this Case..." instead.
Event structures may not be something you specifically use in LabVIEW with cRIOs, as you do not have the user interface to trigger events. However, Event Structures are a great LabVIEW feature that is often used in LabVIEW programs. What cool applications can you utilize Event Structures with?