The keyboard is a vital link between a computer user and the screen. If the keyboard stops working, that does not necessarily mean you need to replace it. Users can solve some common keyboard problems.
If keys stick or certain keys become unresponsive, dust and dirt are likely causes. Turn the keyboard upside down to try to release the dirt trapped inside. If that doesn't fix the problem, use compressed air to spray a jet of air between the keys, releasing any debris.
Keyboard layouts, set by the operating system, use different alphabets and accented letters for different languages. If you type a key and the wrong letter or symbol appears, your system may be using the wrong keyboard layout. Change the keyboard layout preferences back to your desired layout.
Laptop computers often have a "number lock" setting that turns a section of the keyboard into a numeric keypad. If some letters on your laptop keyboard produce numbers instead, check that you haven't turned on this setting by mistake. A keyboard shortcut usually controls it.