Leadholders require different points due to the variety of applications they are used for:
A blunt point for normal writing and
A very sharp point for drawing
The triangular symbols next to the small holes indicate the different kinds of points.
The fine, sharp point on the left is suitable for drawing, the normal point on the right (shown as being slightly blunt) is for writing.
The holes are used for setting the amount of lead protrusion.
