v4

V4, or v4, is a label used across many industries to denote the fourth version or generation of a product, standard, or document. The "v" commonly stands for "version" or "versioned," while the numeral "4" signals the fourth release in a sequence. The convention traces to early software and hardware development practices and has since spread to APIs, file formats, and product naming. The form is often used in informal references and in official release notes as a shorthand for a major update.

Contexts: In software and firmware, v4 often marks a major revision with new features, architecture changes, or breaking changes from prior versions. In web and application programming interfaces, paths like /v4/ indicate the fourth major API version; clients may depend on a specific version. In hardware, v4 might denote the fourth generation of a device or a variant line. In data formats and protocols, v4 can designate a version of a specification, such as a file structure or communication protocol.

Notes: The meaning of v4 can vary by project, company, or community, so context is essential. When migrating between major versions, developers and users typically consult release notes or migration guides. See also versioning, semantic versioning, API versioning.