The keyboard is an external computer device that is easy to break, and it is also an indispensable computer accessory. Computers are often used, especially by programmers (Yuan), who use them every day. It is easy to have problems with the keyboard. After the keyboard fails, some words or It's particularly annoying not being able to type out numbers. Here pcjson.com provides you with an online testing tool to test the quality of your keyboard keys. Every time you press a key on the keyboard, the keys on the virtual keyboard will be highlighted.