What’s the goal of Minecraft and what can users achieve in this world?

The thing about Minecraft is, unlike most games you set your own goals. Here’s a list of common (and uncommon!) things people have done with Minecraft:

• Building a massive structure
• Recreating real-world objects
• Survival (Deleting map upon dying)
• Making amusing videos
• Creating an adventure map for others to play
• Getting all the achievements
• Proposing to your girlfriend
• Achieving difficult things in the game through ingenuity
• Computation
• Blowing stuff up!

The mechanism that keeps the game going is your own desire to complete the goals you’ve set yourself, and pure, red-hot addiction.

Edit

Some additional stuff people have done:

• Walking and walking and walking (thanks SevenSidedDie)
• Build an epic railway
• Make music
• Find the Far Lands

Minecraft 1.9+

In Minecraft 1.9 and beyond, there are villages, strongholds, abandoned mineshafts and nether ruins to explore. In particular, strongholds will contain portals to The End, in which players can fight The Ender Dragon, a ‘boss fights’. The second ‘boss fight’ has also been added, The Wither. This makes exploration a key part of the game, as well as combat. ‘Hardcore Mode‘ (world deletion upon death) is also an option if you’re after a challenge.

A creative mode has also been added that allows players complete freedom in constructing large structures, compartmentalizing that aspect of gameplay.