qwertytrewq is a certain word used- well I wouldn't exactly call it a word, but it's the kind of thing that you would type to a friend or google search when it's 3: am and you're bored out of your mind and you don't know what else to do.
When you get so bored, you decide to do 2 letters from the left then 2 letters from your right until you run out and you keep going to the bottom of the keyboard until you run out of letters.