Open Source Concepts

1. Free software:

   It is really accessible and can be freely used, changed, improved, copied and distributed by all who wish to do so.
   Eg:
   

   • Linux Kernel
   • My SQL Relational Database
   • Libre Office



2. Open Source Software:

   It can be used freely in terms of making modifications, constructing business models around it and so on but it may or may not be free of charge. In this type source code is made available to the user.
   Eg:
   

   • Apacha HTTP Sever
   • Mozilla Firefox
   • Chromium
   • osCommerce



3. Proprietary Software:

   This software is neither open nor freely available. Its use is regulated and further distribution and modification are either forbidden or requires special permission by the supplier or vendor.
   Eg:
   

   • MS Office
   • Adobe Photoshop
   • Microsoft OS
   • Mac OS X



4. Freeware:

    In spite of having no clear definition of freeware, it is commonly used for software which is available free of cost and which allows copying and further distribution but the source code is not available for modification.
   Eg:
   

   • Team Viewer
   • Skype
   • μTorrent



5. Shareware:

    These softwares are made available with the right to redistribute copies, but license fee has to be paid for the unrestricted use, often after a certain period of time.
   Eg:
   

   • WinRAR
   • PC Write
   • Linux XP



6. Freeware and Open Source Software (FOSS):

   It is computer software that can be classified as both free software and open-source software. Anyone is freely licensed to use, copy, study, and change the software in any way, and the source code is openly shared so that people are encouraged to voluntarily improve the design of the software.