What does 1234 on the handle mean?

That's the logo of Sony PlayStation series. These logos are used in the handles of PS series, and this is patented. Without authorization, other companies may not use it. Keys have different functions in different games, but generally speaking, the O key of the Asian version of the machine is confirmation and the X key is cancellation; The European and American versions are X confirmation and O cancellation. In the system interface, the triangle key can bring up the menu.