An example of proprietary software would be Microsfot Windows and Adobe Photoshop, there is of course a host of others, but these are well known and will give the reader a good idea of what is being discussed here.
Proprietary software describes computer software which is the legal and rightful owner of one person, or party. If another party wishes to use it they need to adhere to a set of terms which have been defined by either a contrat or a licencing agreements. These terms include sharing privileges, use of the software and use of the software’s code.
There are a few free software packages that are available under proprietary terms though. What this means is that the original holders of the software can use dual licencing in order that they may redistribute proprietary versions. Free software that has been released for public use allows anyone to make proprietary redistributions.
There is proprietary software which comes with source code and users can use, study and even modify the software, but they restricted from redistributing modifications to the software by licences or non disclosure agreements. They are also restricted from sharing the software.
Shareware software is proprietary, but it has a limited life and is generally offered on a trial basis, after which it is either disabled, or restriction of use are imposed.
Propreitary software which no longer marketed by its owner and which is used without permission is called abandonware. IT may or may not include source code, but some has its code placed in public by its author. This software is known as free software, not proprietary.
