Catalog: A collection of metadata records about datasets, data services, or data products.

Data: The actual information content stored in systems and used for business operations and decision-making.

DCAT (Data Catalog Vocabulary): A W3C standard for metadata used to describe datasets and data services in catalogs.

Dataset: A collection of actual data, published or curated by a single agent.

Dataset Metadata: Standardized information that describes a dataset without containing the actual dataset.

Data Governance: The framework of policies, processes, and standards for managing data as an asset.

Data Mesh: An architectural approach that shifts from centralized data platforms to a distributed, domain-oriented ownership model.

Data Product: A rational, managed, and governed collection of data, with purpose, value and ownership, meeting consumer needs over a planned life-cycle.

Distribution: A specific representation of a dataset in a particular format.

DPROD (Data Product Ontology): A specification that extends DCAT metadata to describe data products.

Input Port: A service exposed by a data product to collect its source data, described by metadata in the catalog.

Metadata: Structured information that describes, explains, locates, or otherwise makes it easier to retrieve, use, or manage data. This is what data catalogs primarily store and manage.

Output Port: A service exposed by a data product to share generated data, described by metadata in the catalog.

SKOS (Simple Knowledge Organization System): A W3C recommendation designed for representing glossaries, taxonomies, and thesauri; often used alongside DCAT for structured terminology.

W3C: The World Wide Web Consortium, an international community that develops open standards for the web.