The software which is available for certain periods of time for use, of for promoting any company product or all trial version of software is called shareware. In this mostly antivirus software and other like utilities and application falls. Most of antivirus company provides their products for 1 month to try and know about their products how they work. Shareware is a proprietary software.
# note:- Bob Wallace coined the term ‘shareware’ come before the birth of IBM computer.