The basic strategy and doubling down

There's a sad but obvious fact about playing in a casino, whether real or virtual. The operators have worked out how to play the games on offer and set the odds to favor themselves. After all, if the majority did not lose, there would be no money to pay out all the money you win. Needless to say, the casinos have invested time and money into working out every possible variation on the rules and the ways to play under them. So, if you are going to take on the House edge, you have to become as big an expert on the rules as the operators. So let's begin with one of the more interesting rules which decides when you are allowed to double down. This applies when you have received your two cards. If you decide you are going to draw only one more card, the casino rules can allow you to double your initial bet. The different possibilities are to double: