Proprietary software
Software distributed under terms that restrict access to its source code or limit users’ rights to modify, copy, or redistribute it.
Software license: A legal instrument specifying the permissions and restrictions for using, modifying, and distributing software. Its terms establish the rights that make software proprietary.
Free and open-source software: Software licensed to allow users to run, inspect, modify, and redistribute its source code. Its user freedoms contrast with the restrictions characteristic of proprietary software.
Microsoft Windows: A family of proprietary operating systems developed by Microsoft for personal computers and other devices. It is a widely used example of a proprietary operating system.
Vendor lock-in: Dependence on a supplier that makes switching to another product costly or difficult. Proprietary formats, licenses, and services can raise the cost of leaving a vendor.
End-user license agreement: A contract setting conditions for an end user’s use of a software product. Many proprietary programs grant access through these use restrictions.
Free software: Software distributed under terms that preserve users’ freedoms to run, study, modify, and share it. The contrast concerns user freedom, not whether the software costs money.
macOS: Apple’s proprietary operating system for Mac computers. Its controlled licensing and distribution illustrate proprietary desktop software.
Interoperability: The ability of different systems or products to exchange information and work together. Restricted interfaces can make proprietary products harder to combine with alternatives.
Source code: Human-readable instructions from which a software program can be built or interpreted. Withholding it prevents users from inspecting or modifying the program directly.
Open-source software: Software whose source code is available under licenses permitting use, modification, and redistribution. Its licensing model makes source access and collaboration explicit.