Glider

A glider is a customization feature used in Mario Kart 7 and Mario Kart 8. Its main purpose is to allow the player to float safely across gaps or though tracks. Gliders only affect the weight and acceleration stat, along with the hidden air speed and air handling stat.

Mario Kart 7
Gliders first appear in Mario Kart 7. They may affect the weight or acceleration, or even the air speed and air handling. If players brake or get hit with an item while gliding, they cancel their glider.

All tracks in the game, excluding Rosalina's Ice World, N64 Luigi Raceway, and SNES Rainbow Road, utilize the glider.

Mario Kart 8
Gliding returns in Mario Kart 8, and functions exactly like it did in Mario Kart 7.

The only tracks in the game that don't make use of gliding are Toad Harbor, GCN Dry Dry Desert, and SNES Donut Plains 3.

Trivia

 * The Super Glider, Peach Parasol, Flower Glider, Paraglider/Parafoil, and Gold Glider are the only gliders to appear in both games.