Canoeing: paddling of an open, usually non-decked craft, paddled with a single blade in a kneeling position
In the UK canoeing is often used to cover both kayaking and canoeing, although the two disciplines require a very different skill set.
Kayaking: paddling a closed deck boat, with a double-bladed paddle from a seated position.
To see the difference in action (videos):
In racing you’ll hear the following terms:
K1: single seat kayak
C1: single kneeling canoe
C2: two people kneeling canoe
K2: two seater kayak
C4: four person kneeling canoe
K4: four seater kayak
Sprint: Flatwater Racing: the most usual distances are 200, 500 and 1000 metre sprints, or long distance.
Slalom: Timed navigation along a white water course or rapids.