The jungle is a part of the map, which is located between lanes and consist of jungle camps. These camps contain mythological creatures, whom can be killed to receive gold, exp and buffs. These camps range in difficulty from easy to hard and provide different benefits based on each camps.
The easy camps consist of 3 Harpies, which give you exp and gold when you defeat them. The medium camps consist of Dentons, who not only give you exp and gold when killed, but the "boss" Denton from each camp provide you with a buff depending on the camp defeated. The "red camp" provides a physical and magical power buff. The "orange camp" gives a movement speed buff. The "blue camp" provides a mana regeneration and cool down buff.
If you were to split the map vertically in the middle, there are 3 exp camps, 2 blue buffs, 1 speed buff, and 1 red buff located on each side of the map.
There are 2 more camps, located in the middle of the jungle on each side of the map. These are considered the most difficult camps, and they usually require your team's full participation. These camps do reward you richly, however. The "Gold Fury" is a giant, golden harpy that provides extra gold to your entire team when it is destroyed. The Fire Giant is a giant man with a hammer that lives inside a volcano. (pretty scary) he can summon lava to damage anyone that touches it. He grants a very large power and regeneration buff to your entire team.