In animals, vocalization is a means of communication generated in many cases by their primitive versions of vocal chords.

In birds, it may be achieved by whistling but can communicate a number of things including danger.

It is also used to describe the noises made via the blowhole of mammalian sea creatures such as whales and porpoises.

In humans, it is a special means of communication called speech.

In languages with consonantal alphabets (sometimes inaccurately termed abjads), vocalization refers to the process of adding vowel markers (Arabic tashkil , Hebrew niqqud). See also: Arabic alphabet, Tiberian vocalization, Syriac alphabet.

In phonology it can refer to the replacement of a consonant sound with a vowel sound, e.g. for milk in many accents of English or [hiːɐ] for hier in German.