Module Metadata is a modulemd yaml document that contains information about a <<Module Artifact,Module Artifact>>. Module Metadata can be found in modules.yaml in the repodata.
For more information see xref:building-modules/fedora/defining-modules.adoc[this topic].
The standard for yaml modulemd files is defined https://github.com/fedora-modularity/libmodulemd/tree/main/yaml_specs[here^].
This abbreviation describes the new naming conventions for <<Module,modules>> i. e. Name:Stream:Version:Context:Architecture.
For more information see xref:architecture/nsvca.adoc[this section].
(Module) Stream Expansion
Stream expansion is a feature of Modularity. It enables you to build your module streams for several OS releases. The <<Module Metadata (modulemd),Module Metadata>> specifies how and for what major releases of an operating system, your package will be built.
For example: you can specify that mariadb:10 can be built for f29, f30, f31 and not built for f28 with specific options for each buildroot.
For more information see xref:architecture/stream-expansion.adoc[this section].