6. licensed software

• Which major software licensing methods exist? When payments are expected?

  1. Licensed software: copyright protected by company or individual; usually requires an up-front fee before use. Demo versions may be available -- generally not full-featured -- will have an expiration date.

  2. Shareware: copyrighted by the author, but distributed for free -- "try before you buy." Payment -- expected after the trial period if the software continues to be used. Some features may remain locked -- contingent on payment.

  3. Freeware: copyrighted by the author -- available free of charge. Some authors request a nominal donation for continued development but there is no requirement for payment for continued use of the program.

  4. Open-source: public domain software -- not copyrighted -- free for all users. Linux community open source software comes with the program source code -- users can freely modify the program.