<P> In 1983, binary software became also copyrightable in the United States by the Apple vs. Franklin law decision, before that only source code was copyrightable . Additionally, the growing availability of millions of computers based on the same microprocessor architecture created for the first time an unfragmented and big enough market for binary distributed software . </P> <P> Most software is covered by copyright which, along with contract law, patents, and trade secrets, provides legal basis for its owner to establish exclusive rights . </P> <P> A software vendor delineates the specific terms of use in an end - user license agreement (EULA). The user may agree to this contract in writing, interactively on screen (clickwrap), or by opening the box containing the software (shrink wrap licensing). License agreements are usually not negotiable . Software patents grant exclusive rights to algorithms, software features, or other patentable subject matter, with coverage varying by jurisdiction . Vendors sometimes grant patent rights to the user in the license agreement . The source code for a piece of software is routinely handled as a trade secret . Occasionally, software is made available with fewer restrictions on licensing or source - code access; such software is known as "free" or "open - source ." </P> <P> Because license agreements do not override applicable copyright law or contract law, provisions in conflict with applicable law are not enforceable . Some software is specifically licensed and not sold, in order to avoid limitations of copyright such as the first - sale doctrine . </P>

Which type of software has no restrictions from the copyright holder and can be modified