--- title: Decks page_id: decks-index --- Crazyflie expansion decks add new sensors and functionality to the Crazyflie. The firmware part of each deck is implemented as a [deck driver](/docs/development/howto.md) and adds functionality spcific to the deck. Read more about the functionality and implementation of each deck in the list below. * [Active Marker deck](/docs/userguides/decks/active-marker-deck.md) * [Micro-SD card deck](/docs/userguides/decks/micro-sd-card-deck.md) * [Buzzer deck](/docs/userguides/decks/buzzer-deck.md)