Creepers are hostile mobs that makes use of a suicide-style attack: It approaches players and then explodes, causing damage to players as well as surrounding blocks and entities. Creepers spawn in the overworld at night, and in locations with a light level of 7 or less, just like most other hostile mobs; however, unlike Zombies and Skeletons, Creepers will not catch fire in direct sunlight, and those spawned in darkness will nevertheless continue wandering and attacking throughout the day in any physically accessible area until they are killed or despawn.
Creepers are especially dangerous mobs due to their near-silent approach, save for light footsteps and a signature 'burning fuse' hissing noise that often signifies it's already too late. Their explosion is devastating at short range, to both entities and structures.
Creepers run from cats and ocelots, and will even ignore the player to run away when a feline is too close. As cats can be acquired and controlled by the player, this provides an important avenue of defense from Creeper attacks.
Creepers have gained notoriety and infamy among Minecraft players for their infuriating habit of sneaking up on the Player to inflict devastating damage following an all-too-short warning sound. They have arguably become the most recognizable image from Minecraft, as well as the game's unofficial mascot.

You can find this in the Minecraft wiki Article

A person who responds thusly when called a creeper: "Uh, do I look like a giant, green, penis-shaped monster to you?!"

A strain of marijuana that circulated for some time during the mid 1980's. Generally thought to have been hydroponically grown, it was so-called because of its tendency to not produce large headrushes during the act of smoking, the high instead "creeping" up on you 10-15 minutes later. Sometimes referred to as "creeperweed."

A green hostile mob that has the ability of charging toward it's opponent and blowing up in your face or could instantly kill you depending on level of the minecraft game.

A green four-legged creature who's insides are wired explosives. It stalks you, making no sound of its movement except the crunch of grass behind you until you turn to face the green monstrosity of which flashes white and ssSS's UNTIL- Boom. Then you lose your diamond pickaxe and respawn far from your location and slaughter millions of them in rage only to realize that.... It just wanted a hug.

Old people that show up at younger peoples parties. For example, a 35 year old guy that comes to highschool kid's parties and stands around and drinks but doesn't socialize.

1.Anyone who defies social and/or etiquette norms by acting in a particularly odd manner. This can be achieved by staring at someone for long extended periods of time, bringing up topics that aren't socially acceptable in conversation, or just being plainly and unabashadly creepy to those around him/her.