The internet's ancestor crashed after transmitting just two letters of its first message

On 29 October 1969, a UCLA team led by Leonard Kleinrock tried to send the word 'LOGIN' over ARPANET to a computer at Stanford Research Institute. The system crashed after transmitting only 'LO' — making 'Lo' the accidental first message ever sent over what became the internet.

— Leonard Kleinrock, The Day the Infant Internet Uttered its First Words — UCLA Engineering retrospective account