Definition - What does Keypad mean?
A keypad is a set of buttons or keys bearing digits, symbols and/or alphabetical letters placed in order on a pad, which can be used as an efficient input device. A keypad may be purely numeric, as that found on a calculator or a digital door lock, or alphanumeric as those used on cellular phones.
Techopedia explains Keypad
Aside from the row of number keys found on the upper portion of a computer keyboard, a separate numerical pad is also located on the right side for efficient data entry. For more compact computers such as laptops and notebooks, external plug-in keypads may be purchased separately.
Phone keypads are typically alphanumeric, allowing the user to enter names and text messages. They also provide an easier way of remembering phone numbers. For instance, 1-800-DELIVER is a way of marketing a food chain delivery service, but it's easier to remember than the actual number customers would call (1-800-335-4837).