Simple definition
Sonatype Nexus Repository stores and distributes software artifacts and dependencies including Maven packages, npm modules, and container images.
Purpose and use
Sonatype Nexus Repository centralizes storage and distribution of artifacts used by development and deployment tools.
How does it work?
A hosted repository stores internal artifacts; a proxy caches an upstream source, and a group can expose several repositories through one endpoint.
Example and verification
For a missing dependency, check repository format, source ordering, permissions and the client's version policy.
Points to watch
A repository cache does not guarantee authenticity or absence of vulnerabilities. Publication permissions and artifact provenance require control.
In short
The repository supports availability and traceability when publication, retention and access rules are managed.