There are several theories but the two that seem to stick are that sleep: allows your body to replenish energy stores and repair itself. gives you the chance to save energy. Sleep may also aid learning and give our bodies time to organise all the memories of the hundreds of events we experience every day.
Softwood is also used in the production of paper, and for various types of board such as MDF (medium-density fiberboard). The finer softwoods have many special uses. they are used for making window frames,doors,frames,t.v. stands,flooring and beds.
As it turns out, a hardwood is not necessarily a harder material (more dense) and a softwood is not necessarily a softer material (less dense). For example, balsa wood is one of the lightest, least dense woods there is, and it's considered a hardwood.The distinction between hardwood and softwood actually has to do with plant reproduction. All trees reproduce by producing seeds, but the seed structure varies.vergreens do tend to be less dense than deciduous trees, and therefore easier to cut, while most hardwoods tend to be more dense, and therefore sturdier. But, as the classification of balsa wood demonstrates, there is no minimum weight requirement to become a hardwood.