The 24th letter of the English alphabet is X. In the standard modern English alphabet, the sequence ends with U, V, W, X, Y, and Z, placing X in position 24 of the 26-letter set.
X descends from the ancient Phoenician letter samekh through the Greek letter chi and later Latin writing. Its English name is pronounced “ex,” and its lowercase form is x. The letter has several common sounds, including the /ks/ sound in “box,” the /gz/ sound in “exam,” and a /z/ sound in some words such as “xylophone.”
A frequent mix-up is counting from the wrong end or confusing X with Y, which is the 25th letter. X also appears in many systems beyond ordinary spelling: it can represent an unknown quantity in mathematics, a multiplication sign in informal writing, or the Roman numeral 10. In alphabetic order, however, its position is unambiguously 24.