A DK Barrel is a very common barrel that you will find in all of the Donkey Kong Country games, as well as many other recent DK games. Breaking one will release a defeated Kong that is no longer with you, making them playable again. Most DK barrels are sitting on the ground, but some are in mid-air, and break at contact with a Kong. They are a lot like Vine Barrels in the way that they break upon contact with anything when thrown, even the floor. If thrown at a hidden entance to a bonus room in the wall, they can break and uncover it. They, of course, can only be broken if you only have one playable Kong with you.
DK Barrels have appeared in every Donkey Kong Country and Donkey Kong Land game, and they return in Donkey Kong Country Returns. In Donkey Kong Land 2 and Donkey Kong Land III, all DK barrels are found in mid-air. This makes it so you cannot use them for throwing into anything.
In Donkey Kong Country: Tropical Freeze, each Kong gets their own designed barrel with the Barrel rotating between the 3 when choosing.