Reading numbers
Level: Basic
The number on an open cell is the mine count among its 8 neighbors.
Every deduction in Minesweeper starts from a single number. The number on an open cell tells you how many mines are hidden among the up-to-eight cells surrounding it.
For example, if a cell shows 1, exactly one of its eight neighbors is a mine. A 2 means two; a 0 (blank cell) means there are no mines nearby at all, so it automatically opens up a wide area.
Once you truly grasp this one rule, every other technique is just a matter of combining these numbers. Start by getting into the habit of telling apart the 'already-open cells' and the 'still-closed cells' around a number.
Related techniques
Flagging certain mines
If the closed-neighbor count equals the number, they're all mines.
BasicOpening safe cells
If the adjacent flag count equals the number, the rest are safe.