Labials contain consonants that are articulated by the use of lips.
Bilabial sounds are produced with both lips. That means the active lower lip may contact the passive upper lip. The English bilabial sounds are [p], [b], and [m].
Labiodental sounds are produced by a movement of the lower lip against the upper teeth, which means that the active lower lip may contact the upper teeth. The English labiodental sounds are [f] and [v].