ppap stands for pen pineapple apple pen. a japanese person name piko taro that makes videos has made ppap popular around the world.
ppap! ............i have a pen......i have an apple.......UH! APPLE PEN! I have a pen.........i have pineapple..........UH! PINEAPPLE PEN! APPLE PEN........PINEAPPLE PEN.........UH! PEN PINEAPPLE APPLE PEN!