Git is a distributed version control system, meaning every developer's clone contains the entire project history, unlike centralized systems where a single server holds the authoritative history.
Key Points: • In centralized VCS like Subversion, most operations require network access to a central server; Git performs commits, diffs, and history browsing entirely offline. • Every clone is effectively a full backup of the repository, which makes Git resilient to server loss. • Branching and merging are lightweight and fast in Git, encouraging frequent, isolated feature work that's cumbersome in many centralized systems. • Git uses SHA-1 (or SHA-256) hashes to identify commits, giving strong integrity guarantees about the content of the history. • Collaboration happens by pushing and pulling between repositories rather than checking in and out of one central store.
Example: A developer on a plane with no internet can still commit, branch, view history, and diff files locally in Git, then push everything to the remote once they're back online, something a centralized system like SVN can't do.
Interview Tip: A concise interview answer is:
"Git is distributed, so every clone has the full project history and most operations work offline, unlike centralized systems that need a connection to a central server for almost everything. That also makes branching and merging much cheaper in Git."