Shareware and Freeware are two common terms defining how software is distributed.

Shareware

Shareware is a licensing model that allows the end-user to evaluate a software product free of charge for a period of time or number of uses (the Evaluation Period). At the end of the Evaluation Period, the end-user must do either one of two things:

  1. Purchase a full license to continue using the software, or
  2. Uninstall the software with no further obligation.

During the Evaluation Period, the software may impose restrictions on what the end-user can do with the software: Features may be fully or partially disabled, time limits may be imposed, etc.

Some synonyms for shareware include: Trialware, Try-Before-You-Buy.

Freeware

Freeware software does not require any fee to be paid for continued use of the software.

Freeware can have limitations and restrictions on use.

Charityware

A variation on Shareware, this requires users to make some kind of donation to a specific charity, normally one designated by the software’s author.