On his 72nd birthday he was so often photographed that he finally had enough. And for fun he sticks his tongue out at the next photographer! This photo becomes famous around the world. His wild hair is also very unusual as other men look much more tidy. For this reason Einstein is called sloppy. But as already mentioned, he doesn't really care.
Here you can see a picture of Albert Einstein that a pupil from a Brandenburg school painted. His trademark wild hair can be clearly seen.