Bridge computations

The tables show what you can score on a contract that makes. Some of the fields are coloured like this, like this, or like this. They represent doubled or redoubled contracts. That a field has been coloured in this way, means that the contract scores better than the corresponding contract bid to the limit.

Example:
1 minor, not vulnerable, doubled, made with an overtrick scores 240 points. If instead you bid 2 minor and it makes, you get 90 points. So it's better to play it as 1 minor doubled.
If you bid 2 minor and get it doubled and it makes, you get 180 points. It's still better to play it as 1 minor doubled.
However if 2 minor is redoubled, you get 560 points which is better than the other results.

Therefore the field corresponding to 1 minor, not vulnerable, doubled, 1 overtrick, has this colour.

This colour means that there is no (re)doubled contract on a lower level that scores as much (same suit and number of tricks). It must be bid to the limit.

This colour coding may seem superfluous - you can't order the opponents to double. Nevertheless I think that it gives you an idea of some conditions about doubled/redoubled contracts, and anyway one can just ignore the colouring.