It is explained as a kind of freeware wich the author places a request for payment, usually by accompanying documentation files or in an indication made by within the software itself.
This payment may or may not include support or certain functionalities.
Copyrighted software that is available free of charge on a trial basis, usually with the condition that users pay a fee for continued use and support.
Understanding the difference between the 2 is imporant.
Shareware usually is a trial basis with limited time period. In many cases, you can continue to use the software after trial period, however, it’s recommended that you determine if you have a use, you purchase a license copy of the software.
Freeware is usually just free, and no cost incurred to utilize.
There may be options to license a copy, however, may not be mandatory