All beds do not need box springs. Many mattresses work fine on platform or slat bases. Although box springs are popular in North America, in most other parts of the world alternate mattress supports are more common.
Box springs give a different feel to a mattress than a platform or slat base. A box spring produces a softer effect with a bouncier feel. Platforms and slats produce a firmer mattress surface. Some mattress manufacturers recommend that their mattresses only be used with new compatible box springs. When buying a new mattress, it is important to check to make sure that the warranty remains in effect if the mattress is placed on an alternate support base.