PU

On Snapchat, people message "pu" to get others to "pop up" and message them. Most people use it when bored and looking to interact with others.

Snapchat is a social media service where people can send messages with text, videos, and pictures. PU gained popularity on Snapchat in 2017, but it is unclear who first used it. However, the acronym comes from the notification the service pops up when someone contacts you.

Teenagers and young adults typically use PU since older people usually don't know what it means. For example, a teenage girl may be bored waiting for a ride from their parents, so they message "pu" to their friends.

PU stands for "Parallel Universe," a term used by Nintendo 64 (N64) gamers who play Super Mario 64 (SM64). It is an area of a course in Super Mario 64 that is meant to be out of bounds but is accessible to a player due to a glitch in the game.

The glitch is in the game's coordinate system that allows players to escape the course onto a duplicate course, or "parallel universe." However, the PU is rather desolate since it has no objects, items, enemies, or walls. The video below from the pannenkoek2012 YT user provides further explanation about PUs beginning at the 10:38 mark.

The acronym is only used by Super Mario 64 gamers so if you do not play the game, you will most likely never hear or see the term. N64 gamers may include older adults who played the game on the original console back in the 1990s or younger gamers playing N64 gamers on some type of emulator.