closedsource

Closed-source, also called proprietary software, refers to software whose source code is not publicly released and is owned by an individual or organization. Access to the code is restricted, and distribution occurs through compiled executables under a license. It contrasts with open-source software, in which the source is publicly available and modifiable.

Licensing and distribution: The vendor retains copyright and grants usage rights through licenses that restrict copying, distribution, modification, and reverse engineering. Updates and features are controlled by the vendor. Some closed-source software uses software-as-a-service models where the code runs on remote servers; users interact via client software but do not obtain code.

Scope and examples: Found across consumer, enterprise, and embedded software. Prominent examples include operating systems, office suites, and many commercial apps such as Windows, macOS, Adobe Photoshop, and Oracle Database. Open formats or standards may be supported, but the implementations are typically proprietary.

Development and governance: Development is typically controlled by a single vendor or a few license-holders with centralized decision-making. This can enable a cohesive user experience and integrated services but may limit interoperability and community contributions. Security is often validated via internal testing and third-party audits on request.

Criticism and defense: Critics argue closed-source reduces transparency, hinders interoperability, and risks vendor lock-in. Proponents note intellectual property protection, clear monetization, and controlled updates. Licensing practices and price models are common considerations for users and organizations.

See also open-source, proprietary software, source-available software.