MMS stands for Multi Media Service, which is used for sending various types of files over cellular networks, not just images. The Vonage Messages API supports four different MMS message types: image, audio, video, and vCard. MMS can be used for promotional messaging, transactional uses such as instructional videos or proof of parcel deliveries, and can add an extra dimension to SMS messaging by promoting products with images, videos, or sound clips. To send an MMS message using the Vonage Messages API, a POST endpoint is used, which requires an Authorization header and a JSON payload containing the message type, file URL, to and from numbers, and channel information. The Vonage Messages API can be used to send MMS messages in the USA to numbers on certain networks, such as AT&T, T-Mobile, and Verizon. An example application was built using the Vonage Ruby SDK to send a daily MMS message containing a random xkcd comic image. The application uses environment variables, a gem called get_xkcd for interacting with the xkcd API, and the vonage gem for sending the MMS message.