If you find that all the menus are suddenly missing from your web browser, leaving the web page filling almost the entire screen, you have probably switched into full-screen mode accidentally. This is easy to fix: push the F 11 key to set things back to normal. It is

also possible to switch back using the mouse. In Firefox, the Restore button should still be visible in the upper right-hand corner of the screen. Click on this to return to the normal viewing mode. When using Internet Explorer, the Restore button is not visible at all times, but by holding the mouse cursor at the very top of the screen a toolbar including this button will slide into view. Click on the Tools button, then Full Screen to switch back.