Split keyboards are often categorised in two styles: two separate pieces or a single unit with a split layout:
Split keyboard with two separate pieces
This keyboard design features two parts, where each half contains a portion of the keys. The two parts are either connected via a cable or a ball joint or paired to your computer wirelessly. Some designs also allow you to change the vertical angle of the keyboard pieces.
Split layout keyboard
This kind of keyboard is made of one piece and uses the same layout as a standard keyboard. The only difference is that the keys are split into two groups and are usually sloped or curved to help you type with your wrists in a natural position.