"Events" allow you to define Javscript actions that take place when a certain "event" happens, such as a mouse click, or a key press on a particular element within your page
How to attach an "Event" to a page element:
In this example, add a button to the page, which when clicked will display a "Hello World" message:
button to insert a new button into your page
Select a "Standard Button", and set the "Text to display on button" to "Click Me"
Now in the "Event" drop-down list, select "Mouse: Click", and click the "Add" button
From this "Script Categories" list, select "Messages -> Alert Box"
You will then be prompted to enter a message. Enter "Hello World!", and click "OK". This window will then close, taking you back to the original "Insert Form Button" window
Click "OK" to place the button onto your page
Preview your file, and you should see something similar to this:
..clicking this button should display the message "Hello World!"