The Banana (also known as the Banana Peel) is arguably the most common item in the Mario Kart series. A Banana Peel causes a vehicle to spin-out if the vehicle touches the slippery item. These items are probably the least effective item in Mario Kart, but tripping on a bunch can effect you greatly. Even one banana can decide whether you're in 1st place or 2nd place.
A Banana can be used as an offensive or defensive Item. A player can throw a Banana out in front of their kart to try to trip up the racer in front of them. They can also be deployed behind the kart, so the driver behind you will be greeted by a deadly smiling Banana and spin out.
For defense, a Banana can also be deployed and suspended behind the kart (This feature is not present in Super Mario Kart). The Banana now acts as a shield against other Items such as a Red Shell or a Green Shell. Also, they can act as a barrier against opponents who try to knock you off the edge. In Mario Kart 8, Triple Bananas circle around the racer, so they can be used by running into an enemy racer, making them spin out.
There is also a larger variant exclusive to Mario Kart: Double Dash!! called the Giant Banana. When a driver hits a Giant Banana, the fruit will split into three normal Bananas. This gigantic special item can only be used by Donkey Kong, Diddy Kong, King Boo and Petey Piranha, who are able to use any special item.
The Banana Bunch is an item exclusive to Mario Kart 64. It is a row of five Bananas that trail the user's kart. Hitting another racer with the trail causes all the Bananas to drop and a crazy sound effect to play. This is one of the few normal items that have only appeared in one incarnation; although a Triple Banana variant took its place in Mario Kart DS and onward, neither version appeared in Mario Kart: Double Dash!! and also in Mario Kart 64, it is possible to prevent spinning out from hitting a Banana. It is accomplished by holding the B button (brake) until a musical note appears over the character's head. This can only be done if the racer is driving straight; hitting a Banana going into a turn will always yield a spin-out. Though done a little differently, this is also possible in Mario Kart: Super Circuit (by tapping the "B" button)
The Triple Banana is served as a replacement for the Banana Bunch, instead of being a row of five bananas, it's now a row of three bananas. Like the Banana Bunch, it didn't appear in Mario Kart: Double Dash!!. It appears in Mario Kart DS, Mario Kart Wii, Mario Kart 7 and Mario Kart 8.
- When you set the items to bananas only in Mario Kart 7, there is a small chance to get a Lucky Seven, which gives you seven bananas surrounding your kart.