and you need have no worries about security. You decide which files and/or folders will be accessible to your helper, and you can terminate the whole process with a single mouse click if you're not happy.
Your helper will see your desktop on his/her screen, and you'll see the mouse pointer moving on yours. Windows and menus will open and close as the helper controls your machine.
Use this facility with confidence - it's a very welcome addition to the Windows tool kit.