Playing (the windows version) of minesweeper on expert level involves a bit of tactics/speed and the rest is simple logic.

tactics/speed
- First of all, you need to get an area cleared as soon as possible. The easiest way is just to click around randomly. From there on, see “logic”.
- Secondly, you don’t need to mark the mines. If you leave them blank, they will fill up automatically when you finish the grid, saving you 99 mouse clicks. This sounds contradictory, as the sole aspect of the game seems to be clicking around, but the 99 clicks make up quite a lot of time if you’re getting fast (e.g. my record is 104 seconds).
- Third aspect, but certainly not less important, is your mouse (and mouse pad, if you’re using one). Allow your motor control with the mouse some time to get used to minesweeper, and keep the ball clean.

Logic
The rest is simple logic most of the time. Ok, there are those awkward corners you sometimes have a 50% chance, but except from that, it is logic. If at one area you can’t find numbers/mines, go on with another area and the problem-area will solve itself.
Minesweeper is even used in introductory math classes to teach the students basic aspects of reasoning, as it is based on “if…and… then…” not only per square with a number, but combining the information of the numbers in the squares in close proximity. Like IF this square has nr 2, AND of the 8 neighbouring squares 6 have numbers, THEN the remaining 2 must contain mines.

However, I suspect Microsoft that they made the game a bit easier, because I find often the same structure of mines and numbers (or I’ve played it too often), whereas it takes me more time with the linux version (but at the moment I still blame my mouse for that).
And for you readers who are bored with the squares: minesweeper also exists with other geometrical shapes and combinations of geometrical structures :)

update 7-6-2003: my latest best score is 86 seconds, the double amount of time of the world record, when I actually had to write my dissertation. (I use minesweeper as a 'distractor' in order to organise my thoughts on what and how I should write all the theory stuff of the research).