> For the complete documentation index, see [llms.txt](https://gitbook.semantify.it/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gitbook.semantify.it/domainspecifications.md).

# Domain Specifications

A Domain Specification (DS) is a formalized, machine-readable, and structured document that defines syntactic and semantic, domain-specific constraints for Schema.org annotations. The main purpose of Domain Specifications is to define a standard to which schema.org annotations have to comply, this is checked during a process called "domain-specific verification". Domain Specifications can also be used as a dynamic guideline for the creation, mapping and presentation of structured data.

Since the concept of Domain Specifications has been enhanced multiple times, documentation for the different versions is provided:

* [DS-V7](/domainspecifications/ds-v7.md) - Stable (latest in use)
* [DS-V6](/domainspecifications/ds-v6.md) - Unused
* [DS-V5](/domainspecifications/ds-v5.md) - Deprecated 
* [DS-V4](/domainspecifications/ds-v4.md) - Deprecated
* [DS-V3](/domainspecifications/ds-v3.md) - Deprecated
* [DS-V2](/domainspecifications/ds-v2.md) - Deprecated
* [DS-V1](/domainspecifications/ds-v1.md) - Deprecated

Note that the term "Verification" was introduced as our standard to define the process of checking the compliance of given data based on a given domain specification. Before that, we used the term "Validation", which could still appear on some parts of this documentation.