Welcome to the Snake manual!
Here you should get the required information for playing.
First, after launching the game, you'll be requested to choose a level in the range 0-9. Use the number keys for that.
Secondly, the keys to control the game:
← → ↑ ↓ - The arrow keys are used to move the snake in all of the directions: Left, right, up and down.
S - Toggle on/off the in-game sounds.
M - Toggle between three music modes (though not really music ;P):
Q - Quit the game, and possibly enter the hi-scores table.
P - Pause the game. To unpause you may click P, or any of the above keys to continue with their individual functions.
Alt+Enter - Switch to fullscreen mode from windowed mode, and vice versa.
Whatever is changed with the sound, music and video mode will be saved to the file snake.cfg. Specs on editing it manually are given later.
This game is made out of 21 levels, including level 0 - The practice level where you're practicing yourself in different speeds.
For each level you finish, you get one more trial in case of a failure. This is also called an extra life.
At first you begin with one life which you're using at the moment, and for each level you finish you get an extra life.
After completing the latest level you get an extra life as well, thus increasing your score by a single point.
ATTENTION: If in any level the snake crashes into itself, you lose a life.
- A block. Watch out of those, as they'd make you lose a life (unless you're in EAT MODE).
- A normal red apple. This would just make the snake one cell longer.
- A yellow apple. This would make the snake one cell shorter, unless the snake's length is just of a head.
- A black apple. This would let you eat the blocks in EAT MODE! Well, until you get another kind of apple.
- An unknown apple. While it surely acts like one of the above mentioned apple, you can't tell how until you get it.
NOTE: After taking a black apple, you should avoid taking any other kind of apple or you'll get out of EAT MODE.
(There's an exception, when you get an unknown apple which acts like a black apple; But you can never know until you get it.)
Anyway, in EAT MODE you should be able to eat ALL of the blocks. Well, apart from passing through any of the snake's cells.
You should be aware of above comment related to eating any other kind of an apple. In addition, you should be noted that black apples are RARE in comparison to the other kinds.
On the side of the screen you should see something like this:

When the “EAT MODE!” message appears you can eat all of the blocks. That's assuming you've taken a black apple (or a corresponding unknown apple).
The number near the “UP” letters indicates the amount of lives left (including the currently used one).
At the bottom is the number of the current played level. In the case of the practice level (Level 0) you should see “PRACTICE” instead.
How's the final score determined?
Well, the latest completed level is known. The amount of extra lives left from that level is known as well.
The final score is: The latest completed level + The amount of extra lives from that level.
For instance, let's say you've reached level 17 but haven't completed it. Therefore, we're talking about level 16. In addition, let's assume you've finished level 16 with 9 lives. Adding the extra life you've got, it makes a total of 10 lives.
Therefore, the final score is 16 + 10 = 26 points.
And now, to the most extreme example: In case you start playing from level 0 and finish the game without losing a single life, then you finish with 21 lives. But we shouldn't forget the extra life you get at the end, so it's a total of 22 lives. Because level 20 is beaten, the final score is 20 + 22 = 42 points. This is in fact the highest possible score.
NOTE: If you've pressed the button to close the window, your progress in the game will be lost. However, let's say that you press 'Q' in level 17 after finishing level 16 with 9 lives (plus the extra life). Your final score would still be 16 + 10 = 26 points, and you'll get the same chance to enter the high scores table.
Anyway, in case you do enter it, you'll be requested to type your name (or whatever you wish to).
The contents of the configuration file snake.cfg should look like the following:
sound 1
music 1
fullscreen 0
The possible values for each term and their meanings:
0 - For everything, disabled (e.g. windowed mode).
1 - For everything, enabled. There's an exception with the music:
2 - In the case of the music, classic music mode (like in the original DOS version of the game).