There are two reasons to use Security. First, you don't want family, friends or strangers seeing or stealing your data. Second, you want your Palm Pilot returned to you in case you lose it and a yokel (a not-smart person who doesn't use a Palm Pilot) picks it up.
If you want your data to be secure from snooping eyes, use the Security feature, that is, lock your device. In order to begin using Security, go to the Security app. It will be obvious how to use it.
When you turn on your Palm device, if it was not locked (Security OFF), it displays the app and the screen you were most recently working on. If you turn it on after locking it (Security ON), it will display:
This handheld computer is owned by:
<your address line 1>
<your city, state, zip>
<your telephone numbers>
<your e-mail address>
Enter password to access this handheld computer:
To enter Owner information, see Preferences, Owner. To turn your Palm Pilot off with Security ON, see Preferences / Buttons/Pen.