Takeout doubles apply over preemptive openings (weak hands with long suits), the same as over one-bids. People don’t always think of double as a bid, so they don’t use them as much as they could. We’re programmed to bid suits! Here’s a typical preempt:
♠ KQJ1075 ♥965 ♦6 ♣1053 You have a good suit, missing only the ♠A, and 6 high card points. A perfect time to open 2♠.
If the hand had another spade, and the same point count, you’d open it 3♠, (♠ KQJ10754 ♥96 ♦6 ♣1053) A preemptive hand shouldn't look like a one bid. It needs to be weak!
The next hand to bid over the preempt should either overcall with a good suit, or double (X) with a good hand. The higher the preempt, the stronger the doubler should be. Over a 3-level preempt, double in the direct seat with 15+. Shape is always important. e.g. 3♦ is opened on your right, you hold: ♠AK62 ♥AKJ4 ♦94 ♣1074. Double would describe your hand well.