A behavior tree is a hierarchical decision structure used in game AI to control how a non-player character chooses actions. Conditions are checked in a tree of selectors and sequences, then the AI executes the first branch that fits the situation. This makes NPC logic easier to read, tune, and debug than a large hard-coded state machine.
In cyber security, behavior trees matter because the same style of branching logic can drive automated bots, sandbox agents, red-team simulations, and even malware or phishing frameworks. Attackers can use decision trees to adapt to host responses, choose next steps after reconnaissance, or switch tactics when blocked. Defenders use similar structures in security orchestration and incident response to make automated actions predictable and auditable. The key security issue is control: when complex AI behavior is built from many branches, teams need strong review, logging, and testing to prevent unsafe or unexpected actions.