Joust is a fight with lances which is a Medieval battle that takes place on horseback, where you charge at your opponent and try to push them off the horse I believe! I think joust is the usual name for this particular sport. The lance is a kind of long wooden stick, perhaps the length of a person, which I guess is helpful because you can use it at long range. A javelin is a stick with a sharp end which you throw as far as you can as a sport. A spear is a battle weapon with a sharp ending, again like the javelin and the lance, they are very long, so it means you can attack people from a distance.

"To joust" is the verb. Javelin, lance, and spear are all "Середньовічна зброя" A javelin is thrown. A lance is used while riding a horse. A spear can be used while on foot or on horseback. (Also a javelin is used in the Olympics now)