Vocalisation is the process of producing sound with the voice, and can be expressed in many different ways. SONG is a form of vocalisation that is composed of words and music, while ARTICULATION is the act of forming words with the mouth. SPEECH is the use of LANGUAGE to communicate, and EXPRESSION is the conveying of emotion through vocalisation. TALK is a casual conversation, while LANGUAGE is a system of communication using words. ENUNCIATION is the clear pronunciation of words, and talking is the act of speaking.