<more pedantic>
In some parts of the world, such as the United Kingdom, kayaks are considered a subtype of canoes. Continental European and British canoeing clubs and associations of the 19th Century used craft similar to kayaks, but referred to them as canoes. This explains the naming of the International and National Governing bodies of the sport of Canoeing.</more pedantic>
<less pedantic>A kayak is a decked boat that one sits in with one's legs extended. A canoe has no deck and one kneels or sits on a seat.</less pedantic>
There are also "closed canoes" that are decked like kayaks but deeper hulled, and you kneel like regular canoes. I had a room-mate that used one in competition.
