LinuxHPC.org/Cluster Builder 1.3

Closed Source

Closed source is an antonym for open source software and refers to any program whose license does not meet the definition of open source software. Generally, it means only the binaries of a computer program are distributed and the license provides no access to the program's source code, rendering modifications to the software technically impossible for practical purposes. The source code of such programs is usually regarded as a trade secret of the company. Access to source code by third parties commonly requires the party to sign a non-disclosure agreement.

Name ambiguity

The phrase "Closed source" is ambiguous because it implies licensing where the source code to a program is unavailable. However, if taken as being an antonym to Open source, it refers to software that does not meet the Open Source Definition, which is a subtly different meaning.

Microsoft's Shared source is an example of licensing where the source code is made available but not under an Open source license. If Closed source is interpreted as referring to software that does not meet the Open Source Definition, then Shared source is an example of Closed source licensing. However, if it is interpreted as simply referring to programs where the source code is not available, this is not the case.

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available under the GNU Free Documentation License. It uses material from
the Wikipedia article "Closed source".}}