Please note that this picture fits primarily to Git.
Other version control systems like VCS are typically used to track changes in text files.
Each version captures a snapshot of the files at a certain point in time and the VCS allows you to switch between these versions.
These versions are stored in a specific place, typically called a You may, for example, revert the collection of files to a state from 2 days ago.
Or you may switch between versions of your files for experimental features.