The kayaker operates a rudder with foot pedals. It will both help the kayaker steer the boat and keep it on a straight course. A skeg is a type of fin that when lowered will drop out of the bottom of the boat. In certain types of wave activity a kayaker will lower the skeg to assist in controlling the boat. If you think there is a possibility you may want to take your boat on some bigger lakes or bodies of water, I'd recommend purchasing a boat with either a rudder or skeg.
Most sea kayaks have hatches located in front and back of the kayak cockpit.
Again, some of the entry-level boats do not come with this feature. Paddle - Paddles, like boats, vary in material and style. The more expensive paddles are made of composites that are as light as a feather. An unfeathered paddle means that both blades of the paddle are on the same plane. A feathered paddle has each blade of the paddle at different angles to one another to help them knife through incoming breezes.