You can secure your files in several ways the most easy way being hiding files and folders, locking files and folder or password protecting them. Users may still have access to all the other files and folders on your system.
In addition to that it will also disable access to copying data from open text files and documents.
The software will also disable the task manager so that no one can kill the prevent or other processes on the computer.
Prevent allows you to lock your computer from unauthorized access by providing hotkeys, you can choose your own hotkeys too.
Rest aside this software is not fool-proof as anyone who knows the hotkey can reactivate all the functions, but nevertheless is can come in pretty useful to keep out your pesky brother or colleague.