For users, a forge is a repository of computer applications, a place where bugs can be reported, a channel to be informed of security issues, etc.
The term forge refers to a common prefix or suffix adopted by various platforms created after the example of SourceForge in 2001.
The GitHub tagline[2] is "The complete developer platform to build, scale, and deliver secure software".
However, in FOSS development communities and since the inception of the first SourceForge fork in 2001, the term forge is still commonly used to designate online collaborative software platforms.
These services may include limited integration with a range of version control system, for visualization and citing code it contains, but that alone is more of a feature than a workflow a developer can use.
Federation and the associated protocol ActivityPub (introduced in 2018) allows forges to communicate with each other about their activities (for instance when issues are created[8] or a commit is pushed[9]).