Ma is the sixteenth of the thirty consonants and the nasal that closes the labial line. It writes a labial nasal, made by closing the lips and letting the breath out through the nose, and it takes low tone as an initial in modern Lhasa speech.
It is one of the five prefixes and one of the ten suffixes, which puts it in the small group of letters that work at both ends of a syllable as well as at its centre. As a prefix it is silent, as prefixes are; as a suffix it closes a syllable and is generally still audible, unlike some of its companions.
Ma is also, by a long way, the letter of Tibetan writing most often seen by people who cannot read Tibetan, because it is the first letter of the syllable that gives the six-syllable mantra of Avalokiteshvara its common name. That mantra is carved on stone, printed on paper, painted on rock faces and rolled inside prayer wheels across the Himalayan world, and the following article takes up what that means for the letter and where the atlas stops.
Ma takes superscripts and the ya and ra subscripts. Beyond the alphabet, the syllable ma is a very frequent element of ordinary vocabulary and is also one of the negative particles of the written language, so like pa and la it is met as grammar quite as often as it is met as the head of a word. Few letters of the thirty are doing as many different jobs on a single page of Tibetan.