Keypads
Keypads vary by the type of panel they are designed to connect to. Advanced panels typically support multiple keypad types. Keypads can be as simple as a 10 numeric buttons (or less) and an indicator light, or as advanced as a multi-display touch panel with graphics support.
Fig1
The keypad above is one of the most basic and provides basic keypad input and two indicators that show arming and zone status. The keypad is also the primary programming interface for the alarm panel. While programming can also be accomplished through other devices (phone, PC), the keypad is usually all that is necessary.
Fig2
More advanced keypads like the one above support other convenient features like the one-touch arming, panic, fire, and different arming modes. This particular keypad supports 2 arming modes. "Stay" allows you to arm the alarm with certain zoned disabled. In most cases, this mode is set to disable pre-designated zones that are connected to motion sensors. Zones connected to windows and doors are armed and exit delays are disabled. The away zone is programmed to arm all sensors with delays intact. The LCD (display) can show a variety of things including zone activity in plain english, time, and a variety of other information. Recently many vendors have started to release "fixed" LCD keypads that support a more limited set of programming options. In general, more function = more cost. The most common keypads have a few special function keys, numbers 0-9, and a LED (light) for each zone.
In order to get started, many panels require you to "register" the keypad to the panel. That is probably the first order of programming after all wiring is complete. Programming is specific to the panel and will be covered in another section.
Wiring keypads typically requires 4 wires (conductors) from the panel directly to the keypad. Most panels also support multiple keypads on the keypad "bus" (same 4 wires). As with the the sensors, wiring distances are limited by the type of panel. Check your manual.
Keypad codes (number of disarm codes) vary by system and typically depend more on the panel than the keypad. Some keypads/systems like that in Fig1 only support only one code. Other support 32 or more codes. This can be important if you tend to give out codes to friends or family.