2048

2048 is the sliding-tile puzzle that became an unlikely global obsession. You play on a 4×4 grid. Every move slides all tiles in one direction; two tiles of the same number merge into their sum when they collide. A new 2 or 4 spawns after each move. The goal stated in the title is to reach the 2048 tile, but the real goal is how far past it you can push.

The design is a masterclass in emergent depth from trivial rules. There is exactly one decision per turn — which direction to slide — yet the strategic space is enormous because every move shifts the entire board. The dominant strategy (keep your largest tile pinned in a corner) is easy to describe and hard to execute under pressure, which is why the game keeps pulling you back. Open-source, freely hosted by the original author, and the template for an entire genre of merging variants that followed.

Use the arrow keys (or swipe on touch) to slide all tiles in that direction. When two tiles of equal value collide, they merge into one tile worth their sum. After every move, a new 2 (90% chance) or 4 (10% chance) appears in a random empty cell. The game ends when no moves are possible.

Strategy: pick one corner — usually bottom-right — and keep your highest tile there permanently. Build a descending chain along the bottom row so merges always feed toward your anchor. Never make a move that forces your anchor tile out of the corner. After reaching 2048, keep going; the real scoreboard is how high a tile you can build before the grid locks.