Stairs are often necessary when building decks between house and patio, pool area. There may just be a small level change requiring a step or two, or a greater level change.
Stair construction follows building regulations, we build our stairs to comply with engineers specifications. Ideally your risers should not be less than 150mm and not higher than 200mm. There is however room for some variation in the look of the staircase/stair, as to whether you choose an open riser with closed stringer as shown in picture 5, or closed risers in pictures 2 and 3.