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Reinforcement Learning

Concept

Fact-checked May 20, 2026

Also called: RL

Reinforcement Learning (RL) is a type of machine learning where an AI learns to make decisions by trying things out and getting rewards or penalties.

What is Reinforcement Learning?

Reinforcement Learning, often shortened to RL, is a powerful approach in artificial intelligence where an agent learns how to behave in an environment to maximize a cumulative reward. Instead of being explicitly told what to do (like in supervised learning), the agent discovers optimal behavior through trial and error, much like how a pet learns tricks through positive reinforcement. Think of a dog learning to sit, it tries different actions, and when it sits, it gets a treat, reinforcing that specific behavior.

The core idea involves an agent, an environment, actions, states, and rewards. The agent performs an action in a given state of the environment, which then transitions to a new state and provides a reward (or penalty). The agent's goal is to learn a 'policy', which is a strategy that maps states to actions, to achieve the highest possible total reward over time.

RL has been successfully applied to a wide range of tasks, including training AI to play complex games like Chess and Go (famously AlphaGo), controlling robotic systems, optimizing industrial processes, and even in personalized recommendations. It's a key component in developing truly autonomous systems that can adapt and learn on their own.

Common questions

What does Reinforcement Learning mean in AI?

Reinforcement Learning, often shortened to RL, is a powerful approach in artificial intelligence where an agent learns how to behave in an environment to maximize a cumulative reward. Instead of being explicitly told what to do (like in supervised learning), the agent discovers optimal behavior through trial and error, much like how a pet learns tricks through positive reinforcement. Think of a dog learning to sit, it tries different actions, and when it sits, it gets a treat, reinforcing that specific behavior.

What else is Reinforcement Learning called?

Reinforcement Learning is also referred to as RL.

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