What is a "Registration Key"? What is a "License Key"?

[ondrej.novak]

Sticky Password 3 and earlier versions required a Registration Key to activate the full functionality of the product. The purchase and software activation process has been simplified for Sticky Password 4, and we have also begun using "License Keys" for the activation code. Note that Registration Keys from Sticky Password 3 (and earlier versions) are not compatible with Sticky Password 4 - and vice versa.

A License Key is necessary to activate the full functionality of Sticky Password 4