GitHub is more than a Git hosting service — it's the de-facto identity layer for open source, the place most CI/CD runs (GitHub Actions), and increasingly the substrate for AI-assisted coding via Copilot. Microsoft's acquisition in 2018 brought the integration with Visual Studio, the package registry, the security advisory database, and Copilot.
For individual developers, the GitHub skills that compound are: writing useful pull requests, designing CI workflows in Actions, structuring releases with semantic-release or changesets, contributing to open source professionally, and using GitHub's issue tracker as a project-management tool effectively.