Minecraft is a block-based game that has a variety of game modes. Some of it are: 

Survival: Survival is a game mode where your main objective is to survive. In this game mode your hunger will decrease according to your difficulty.

Creative: Creative is a game mode where you can do anything you want. You will get unlimited blocks and blocks that are only creative obtainable.

Adventure: Adventure is a game mode where you cannot break blocks unless with its appropriate tool. This game mode is used most commonly in PVP or in adventure maps.

Hardcore: Hardcore is a game mode where you only have one life and your difficulty is locked on Hard mode.