Abstract: Conventionally, high-level communication using the message cannot be achieved. The high-level communication using the message can be achieved by a message transmission device including a component candidate group storage unit capable of storing one or more component candidate groups including two or more groups of component candidates forming a content, an input reception unit configured to receive an input for constituting a content including one or more components determined by the selection of one component candidate from two or more component candidates included in one component candidate group, a content constitution unit configured to constitute the content by using the selected one or more components according to the input, and a message transmission unit configured to transmit a message including the content.