M (letter)

M is the thirteenth letter of the modern Latin alphabet. It is written in two forms: uppercase (M) and lowercase (m). In most languages that use the Latin alphabet, it represents the nasal sound produced by air flowing through the nose while both lips are closed together.

The letter's form consists of three or four straight vertical lines connected together, making it wider compared to other letters. For this reason, in typography and line design, M is typically the widest letter and is used as a measure called an 'em', used to gauge the width of other letters.

History of the letter's form

The origin of the letter is traced to an ancient Semitic sign representing water, known as 'mem'. Its form was a wavy line. The Greeks created the letter 'mu' (Μ, μ) from it, and the Latin alphabet borrowed it via the Greek and early Italic routes. Over centuries, the wavy lines were replaced by straight vertical lines.

Sound

In most languages, M represents the sound /m/. In Somali, M is a regular nasal consonant appearing at the beginning, middle, and end of words—for example in 'macallin' (teacher), 'samee' (do), and 'qalin' (pen). In some languages, M followed by another consonant can shift to the sound of that following consonant, a common phonetic change.

Symbolic uses

M stands for 1000 in the Roman numeral system. In physics and measurement, m denotes 'meter', while M is used as a prefix meaning 'mega' (million). In mathematics and computing, M refers to various units of measurement, such as megabyte. Additionally, M is among the most commonly used letters in company names, brand names, and radio stations.