L

l is the lowercase form of the letter L, the twelfth letter of the Latin alphabet. It is used as a consonant in many languages and is named el or ell in English. The uppercase form is L.

In typography, lowercase l is a tall, slender stroke. In some fonts it can be mistaken for the numerals 1 or the capital I, which has led to typographic conventions to improve legibility, such as using two-storey forms in some fonts.

In science and mathematics, l is a common variable. It often denotes length or distance. In quantum mechanics, the orbital angular momentum quantum number l determines the shape of electron orbitals, with l = 0, 1, 2, 3 corresponding to s, p, d, f orbitals. In crystallography, l is the Miller index associated with a lattice direction or plane, as in (hkl).

Units: The liter, abbreviated L or l, denotes volume. The SI symbol is L, but l is widely used; 1 liter equals 1 cubic decimeter.

In computing, an L or l suffix marks a long integer in languages such as C and Java (for example 1234L). In linguistics, l also denotes the alveolar lateral approximant phoneme.