Dyna is an AI architecture that integrates learning, planning, and reactive execution. It uses machine learning methods for learning from examples and is designed for environments where the agent does not have complete or accurate knowledge of the effects of its actions. The architecture consists of three main components: an action model, a method for selecting hypothetical states and actions, and a reinforcement learning algorithm. Dyna's key idea is to use incremental planning, where the agent learns from hypothetical experiences generated by its action model, to improve its reactive policy. This approach is particularly effective in nondeterministic environments and can handle long-term changes in the world. However, Dyna faces challenges such as the reliance on supervised learning, the need for hierarchical planning, handling ambiguous and hidden states, ensuring behavioral variety, taskability, and incorporating prior knowledge. Despite these limitations, Dyna offers a flexible and powerful framework for integrating learning, planning, and reactive execution.Dyna is an AI architecture that integrates learning, planning, and reactive execution. It uses machine learning methods for learning from examples and is designed for environments where the agent does not have complete or accurate knowledge of the effects of its actions. The architecture consists of three main components: an action model, a method for selecting hypothetical states and actions, and a reinforcement learning algorithm. Dyna's key idea is to use incremental planning, where the agent learns from hypothetical experiences generated by its action model, to improve its reactive policy. This approach is particularly effective in nondeterministic environments and can handle long-term changes in the world. However, Dyna faces challenges such as the reliance on supervised learning, the need for hierarchical planning, handling ambiguous and hidden states, ensuring behavioral variety, taskability, and incorporating prior knowledge. Despite these limitations, Dyna offers a flexible and powerful framework for integrating learning, planning, and reactive execution.