Why did a samurai carry 2 swords?

The traditional long-bladed Samurai sWord is known as a Katana, it is known by its unmistakable appearance. It has a curved, slim, single edged blade, a circular or squared hand-guard, and long grip to accommodate two hands. Its length has varied hugely through history, and it could have ranged from 60 to 74 centimeters. Along with a Katana, a shorter sWord was worn by most of the warrior class. By personal choice that sWord could be a wakizashi, or a shoto. Both of which are similar, but just smaller, another choice of sWord is a tanto, which is smaller still. Both weapons together are called the daisho and they represented the social and political influence and personal honour of the Samurai. Also it may be convenience, for fighting, a smaller sWord may be the sensible choice for a close quarters battle.