What is the difference between electric hammer and electric pick?

Owing to powerful impact, electric pick can directly make impact rupture on object like a hammer or chisel, but its efficiency must be N times higher than manual tools. Electric pick and electric hammer are mainly different in size, electric hammer is high-power and can drill large hole. The both are almost same in principle, and their drill bits have function of rotation and hammering. Impact drill can be used as a common electric drill, and a change-over switch thereon can change it into common drilling and impact drilling..