In this hacker's mind, the online service failed to do a quality job in protecting children from online smut and as retaliation, he created and distributed a virus to as many file libraries of this service as he could. His intentions were to disable the computers of the online service's users so much that they wouldn't be able to connect for days. gif file, it's commonly found on Internet web pages, however it's much smaller than both the .gif image and the .bmp image. .mid - This extension indicates a sound file created with a Musical Instrument Digital Interface. Windows Media Player will open and run these files, however they don't sound like normal . For example, when you're faced with an electronic system, look for a main menu. Most main menus display themselves as soon as a device is turned on, so chances are that if you're standing before a device that shows a bunch of choices to do something, you're looking at a main menu. The buttons on these main menus of course take you to additional menus, which in turn give you even more choices to make. A simple Google or Yahoo search for a particular type of program will yield all sorts of results that point you toward items that you can try before you buy. Be aware however, that because shareware is not commercial software, you may not experience a full program the way you would if you bought the software out of a box. Conditions allow a program to perform an action based on the outcome of a previous command.3 Using this type of instruction, we could instruct a program to do one thing if the "x" variable in our latter example turned out to be 7 days, and then do different thing if the variable turned out to be 3 days. When clicked, a small "x" displays inside a box. Similar to the check box, a radio button allows a user to indicate a single choice among many. Problems with radio buttons and check boxes occur when a user makes one choice, but the interface reacts as if the user made many choices (or none at all).