Mario Kart Wii/Modes

Grand Prix
Compete against 11 other computer-controlled drivers in a 4-race Grand Prix, with the full array of weapons and items available from item boxes scattered around the course. Racers earn points depending on their finishing position in each race. Ending the contest in the top 3 will reward you with a gold, silver or bronze trophy, and may also unlock additional characters and vehicles for you to use.

Time Trial
A race against the clock on an empty track, with no other competitors or item boxes and only three mushrooms at your disposal. The aim is to set the fastest record for completing three laps of the circuit.

Using the Mario Kart Channel, you can download rival "ghosts" to race against in time trial, and see where you rank in your friends list, in your region, or even across the world.

If you happen to be within around 11 seconds of a certain time on a track, you'll unlock a Staff Ghost, an extremely fast ghost done by the Nintendo Staff themselves (hence the Staff in "Staff Ghosts"). They often do crazy maneuvers in-game to be really fast, and even a small slip-up could knock you back 5 seconds, so be careful.

Versus
A single race against 11 computer-controller rivals.

Racing
You, or you and a friend, can both chose different Miis or guest ones and race online with 11 other people.
 * If you play friends, you play a friends-only race which can be a team race.
 * If you play friends worldwide or regionally, you can only play without teams like normal.

You can have up to 30 friends and you get virtual or versus ranking (vr) for racing. You start at 5,000vr. You get more points depending on how many points you have, how many points your opponents have and how many people you are playing.

Battle
Same as above, but you're on teams and if your team loses, you lose points — unless you have a lot or over 10 points, like 10 coins or balloons.