The Latin alphabet is descended from the Etruscan alphabet, which developed from the Greek alphabet . The letters J , U and W were added to the alphabet at a later stage to write languages other than Latin. J is a variant of I , U is a variant of V , and W was introduced as a 'double-v' to make a distinction between the sounds we know as 'v' and 'w' which was unnecessary in Latin.
Many languages add a variety of accents to the basic letters, and a few also use extra letters .
Thorn, which comes from the Runic alphabet , is pronounced like the 'th' in 'three', Eth is prounounced like the 'th' in 'this'.