OK, I am about to try my hand at a British cake recipe. It calls for caster sugar. My question is this: Is caster sugar the same as our regular old granulated sugar? Is it something different?

Caster sugar is much finer than granulated sugar but you can use the granulated sugar for it. The finer the sugar the lighter the texture of the baked good....you could put the granulated sugar in a food processor to grind it finer.....the caster sugar is finer than granulated that says extra fine.