In Japan, it's almost like "lol" or "haha". It comes from the term "笑う", or "warau", and it means "to laugh". The more w's, the more ha's, so to speak.
「変だねww」
"That's weird haha"
「何やってんだよw」
"What the hell are ya doin', lol"
「見たの！？www」
"Did you see that!? Hahaha!"
"That's weird haha"
「何やってんだよw」
"What the hell are ya doin', lol"
「見たの！？www」
"Did you see that!? Hahaha!"
by 塩沢慶子 March 17, 2015