by Jeremy Malcolm, Internet lawyer
The release of Microsoft Windows XP has created renewed public awareness of software license conditions, mainly because Microsoft's new licence is so restrictive. For example, under the terms of its latest licence, business users pay more for their software the longer they take to upgrade, and home users are at risk of having their licence revoked if they make too many hardware upgrades to their computer.
Not all software licences are so restrictive, and it is worth taking some time to look into the major alternatives. Although the precise conditions attached to any software licence can of course only be discovered by reading it carefully, many common types of licence are indicated by the name used to refer to software released under such a licence: for example, shareware, demoware and freeware.
Shareware and demoware describe software that may in general be freely distributed, but may only be used subject to certain restrictions: in the case of shareware a time restriction, and in the case of demoware restrictions on the functionality of the software. For several years there was a question-mark over the enforceability of the restrictions found in shareware licences, but their validity has since been confirmed in court.
Freeware is a term used to refer to software released under a licence which allows it to be used for free. Apart from that fairly obvious attribute, there are not necessarily any other freedoms associated with such software: you cannot necessarily distribute it freely, modify or use it as part of your own software, or sell it.
Software that satisfies all of those additional conditions is called "free software", or "open source software", in recognition of the fact that granting the freedom to modify the software requires that it be distributed together with its source code. Some free software - for example, software released under the GNU General Public Licence or GPL - requires that any software it is incorporated into must also be released as free software, whereas other free software licences - such as the BSD licence - do not have this restriction.
Abandonware is a term used to refer to software that has been "abandoned" by its authors, in that it is older than five years and is no longer sold or supported. However, unless the author has decided to release it as freeware, abandonware is still subject to copyright for at least fifty years. Although users who freely trade abandonware do not consider that they are doing anything immoral - unlike traders of current software, or "warez" - unfortunately the law does not recognise any such distinction.