A game where everything is made of 1 meter cubed blocks.
There are 4 modes:

Survival: Gather resources, build a house, fight health and hunger, kill the Ender Dragon.
Adventure: Same as Survival but you can't destroy blocks.
Hardcore: Survival with no respawning
Creative: Build anything with unlimited resources, free flying, and no health or hunger.
Minecraft is awesome
Current version: 1.3.2

A kick ass game that is being built slowly. The creator is notch, and he programs the game.

Cheap and legal alternative to drugs. This shit will sap your life away.

The single most addicting game known to mankind. Unlike World of Warcraft and other MMORPGs, you pay about $20 for it and it's yours. Those who've broken a previous addiction can stumble upon this and start a new addiction very easily. This drug usually causes anti-sociality, fear of light, explodingpenisphobia, the fear of the exploding penis enemies (creepers), and occasionally having dreams only in blocks.

A game where you can build anything with bricks
There are also different modes:
-Survival: A game where you have to dodge and kill numberious monsters
-Indev: Here you have to gain recrouces to build a fort, weapons and food (only avaialble if you buy the game)
-Free mode: build freely whatever you want with unlimited recources

You can also play online with it with user created servers
but in here you find tons of griefers if you dont protect your creations right

Minecraft is a sandbox game created by Markus Persson, a.k.a "Notch". It is inspired by many games, especially Infiniminer. It has over 400,000 registered players.

There are 6 modes:
Creative: makes you build anything you want, single-player and multiplayer
Survival: a very basic version of Indev, where you have to defend yourself from monsters
Indev: a version which added a number of new features, including crafting and more monsters
Infdev: same thing as Indev except this version added an infinite playing surface

Multiplayer is a part of Creative mode, which allows you to build with other players in servers.
Unfortunately, there are "griefers" that destroy creations including yours.
A survival multiplayer was created in August 2010, which allows players to play Indev with other players.

A suitable alternative to some illegal substance.

Minecraft is a game where when you play it once, u will never go outside or get excersize again. It is like a cheap drug in which you build and remove blocks to make awe inspiring structures.