Speech, language refer to the means of communication used by people. Speech is the expression of ideas and thoughts by means of articulate vocal sounds, or the faculty of thus expressing ideas and thoughts. Language is a set of conventional signs, not necessarily articulate or even vocal (any set of signs, signals, or symbols that convey meaning, including written words, may be called language): a spoken language. Thus, language is the set of conventions, and speech is the action of putting these to use: He couldn't understand the speech of the natives because it was in a foreign language. Speech, address, oration, harangue are terms for a communication to an audience. Speech is the general word, with no implication of kind or length, or whether planned or not. An address is a rather formal, planned speech, appropriate to a particular subject or occasion. An oration is a polished, rhetorical address, given usually on a notable occasion, that employs eloquence and studied methods of delivery. A harangue is a violent, informal speech, often addressed to a casually assembled audience, and intended to arouse strong feeling (sometimes to lead to mob action).