The age is further split into "Old" and "New" periods. The major difference is that in the former people fashioned their tools by smashing rocks together, making for a clumsy and rough finish, whereas we New Stone Agers ground our stone implements. As a result they were smoother and easier to use.
這階段又有新舊之別，大概的區分是舊石器時代人類用敲打方式制石器，成品十分粗糙；像新石器時代的我們，會用磨製方法製造，石器都比較光滑，容易使用。