143 is a popular online numeronym, representing the phrase “I Love You”.
The numbers are meant to represent the number of letters in each word;
I (1) L-O-V-E (4) Y-O-U (3)
There is a legend behind the origin of “143”, ranging back to the turn of the 1900’s, when the Minot’s Ledge lighthouse in Massachusetts would introduce the 1-4-3 flash sequence.
The legend says that Mary Thompson, wife of Winfield Scott Thompson, told their children that the flashes were their father’s way of telling them “I love you”.
“143” started spreading as a way of saying “I love you” in the 1980’s, when pagers were introduced in people’s lives.
Simultaneously, it also appeared online, in early forums and chatrooms.