Blockers in poker are used to inform decisions based on the likelihood of your opponents holding certain cards. If you have specific cards in your hand that reduce the possible combinations your opponents can have, it can influence your strategy. By recognizing the impact of these cards, you can more confidently make aggressive moves, such as bluffs, or decide to fold when you sense strength. Understanding blockers allows you to narrow down your opponents' range, making your actions more calculated and improving your overall decision-making in critical spots.