Traditionally kayaks were solo boats, but a tandem or double kayak is a great way for two paddlers to get out on the water together. Working together in one boat two people can typically go faster than each would go alone. This especially useful if one paddler is less experienced or not as strong a paddler. Instead of being left behind by the stronger paddler, they both end up going faster. Multi person kayaks can either have one large cockpit or a separate cockpit for each paddler. A single large cockpit can be handy if you want to paddle the boat solo as it lets you position yourself in the middle to balance the boat. The separate cockpits allow the use of individual sprayskirts and generally just do a better job of keeping water out of the boat. Tandems or kayaks designed for more than one paddler tend to be longer and wider than solo boats. This accommodates the need to carry more weight. The added width also provides more stability which is nice when two individuals are each doing their own thing. The distance between the seats will effect how easy the boat is to paddle. With the seats close together, if one paddler stops paddling the other may end up whacking into their paddle. Increasing the distance will minimize this problem. This lets each paddler move at their own rate. However, it should be noted that the boat will move a lot easier if everyone paddles in sync with each other.
