Windows Sandbox is an optional feature available exclusively in the Pro editions of Windows 11 and above, allowing users to create a secure virtual environment for testing software without risks. It can be set up by searching for "Turn Windows features on or off" in the Start menu, checking the box for Windows Sandbox, and restarting the computer. The sandbox operates with the same version of Windows as the host and does not maintain its state, meaning changes made within it do not persist after closing. It provides a clean, isolated environment for testing applications, conserving storage space and preventing background tasks from affecting system performance. While it allows safe testing of potentially risky software, it is not a substitute for traditional virtual machines, which are necessary for testing different operating systems or making OS changes.