iMessage allows users to send texts, documents, photos, videos, contact information, and group messages over the Internet to other iOS or macOS users. iMessage is an alternative to the SMS and MMS messaging for most users with devices running iOS 5 or later. The "Send as SMS" setting under Messages will cause the message to be sent via SMS if the sender does not have an active Internet connection. If the receiver has no Internet connection, the message should be stored on a server until a connection is restored.