Could be very basic, but how does OpenGL differentiate between
glVertex3f(10.0f,5.0f,2.0f) and
glVertex3f(1.0f,0.5f,0.2f)
I mean how does it differentiate using absolute cordinates or relative cordinates.
same doubt for color values also!!!
thnks
The first vertex is 10 times farer from origin than the second. 
those vertex calls are in absolute coordinates from the origin. color values are just what they sound like…color values. 0-255 for glColor3ub and 0.0 to 1.0 for glColor3f.
b