A mattress is a pad or mat which is placed above the bed, upon while you sleep. A mattress which is not comfortable could spoil your sleep and cause tiredness for you. There are various types of mattresses available like Foam mattresses, Innerspring mattresses, latex mattresses, visco-elastic mattresses, water beds, air mattresses etc.
These types of mattresses have a strong support structure which is made using coils and shape is retained using border wire. The perimeters of the coils are connected to a wire which surrounds the mattress. At the edges, special springs are used for better support and top layer of mattress has insulation or tough padding for separation from the springs present below it. There could be around 300 to 800 coils inside the mattress which depends usually on its size.