A staircase can become the center of attention in an entrance way or room. Some are used as a focal point of the room and lend an air of glamor to anyone who is descending the stairs.
A straight staircase can be designed three different ways. The first design goes from top to bottom in a straight line. The second design is L shaped. It goes straight up and turns either right or left at a landing. The third makes a T, it goes straight up and turns both right and left from a landing.
A spiral staircase coils around on a fixed axis. Often a pole from the floor to the ceiling and the stairs wraps around it.
In a single-open-under, one side is attached to the wall. It is straight and open underneath. This type is commonly used for basement stairs.
A freestanding staircase allows you to completely pass underneath. The stairs to not do attach to a wall. The only places that are attached are the top step and the bottom step.
The circular staircase is used in lighthouses. They curve around a continuous radius.
An elliptical staircase follows along the side of a curved wall. Each step, starting at the bottom, continues to become longer in length until the middle of the staircase. At this point the steps start a gradual decrease in length at the same rate as they made the increase.