Parts of a stair

you step on the TREAD

The RISER holds the treads-- the riser is the zig / zag part where the treads lay on.

The riser backboard is the face plate you see as you walk up the stairs and your toes hit on.

The Knewal is the post at the top or the bottom of the banister / railing

The ballistars are the poles that are placed under the railing that follow from top to bottom.