Leet or eleet (Leet: 1337, 3l337 or l33t, 3l33t ), also known as "leetspeak"

Leet or eleet (Leet: 1337, 3l337 or l33t, 3l33t ), also known as "leetspeak", is an alphabet used primarily on the Internet for the English language. It uses various combinations of ASCII characters to replace Latinate letters. The term is derived from the word "elite", and the usage it describes is a specialized form of symbolic writing. Leet may also be considered a substitution cipher, though many dialects or linguistic varieties exist in different online communities.

The term leet is also used as an adjective to describe formidable prowess or accomplishment, especially in the fields of online gaming or in its original usage, computer hacking.