Free Software or Freeware

Free software represents a specific program or application that can be used, studied, and modified without any restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions only to ensure that further recipients can also do these things.

There are also some misunderstandings that usually occur like a free software that you don't need to pay for using it but being forbidden to distribute it or improve it in any way. This type of software applications is usually used by different producers in marketing campaigns to promote themselves or a specific product and there is no guarantee that it will stay free.

Absolutely free software is generally placed in the Public Domain and can  be used in commercial programs.

Freeware generally refers to software that is copyrighted, but for which the author solicits no payment, even if the user continues to use it.

Donationware :

The software under this type of license are basically free to use, but the difference between them and those under the Freeware license is the fact theirs publishers accept donations.

Trial Version :

Trial Version is in fact an evaluation period often used to characterize and appraise the value of a specific software application.

Unlike the Full Version, the Trial Version may have also some limitations or unfunctionabilities which could be different from software to software, like :

- time limit (the program could be used for a limited period of time - displayed in a small window when launching the program, with or without all its functions available)

- No Save function - many of the Trial Versions have restricted this function or limited it to determine the user to buy the Full Version and use the Trial just for testing.

A Trial Version application could be Unlocked easily after the purchasing process is done and after receiving the Serial Number, Key or registry file for transforming it to the Full Version.

The Trial Version could be also considered a marketing method chosen by the software publishers around the world.

Shareware :

Shareware, also known as "try before you buy" is pretty similar to the Trial Version and it refers to commercial and copyrighted software applications which could be distributed with the understanding that users MUST pay for it if they continue to use it.

Of course the shareware version of an application could have function limitations even if it's a "Try before you buy".

Demo :

A demo application is a limited type of program and its purposes are to demonstrate what the Full Version is capable of doing. A small amount of what the full version is capable of doing is a general characteristic of the Demo applications too.

The Demo Version is a popular marketing feature mostly used by the Gaming Companies.