These are the systems that don’t rely on a central server to store a project file and all its versions.
In Distributed VCS, every contributor can get a local copy or “clone” of the main repository.
As you can see in the above diagram, every programmer can maintain a local repository which is actually the copy or clone of the central repository which is present on their hard drive. They can commit and update their local repository without any hassles.
With an operation called “pull”, they can update their local repositories with new data from the central server and “pull” operation affects changes to the main repository from their local repository.