Post
Ditch inheritance hierarchies -- just slap components onto entities like LEGO bricks.
ECS is an architectural pattern that breaks game objects into three parts: entities (just an ID), components (pure data like position, health, or velocity), and systems (logic that operates on entities with specific component combinations). Instead of a deep class hierarchy where a FlyingFireEnemy inherits from FireEnemy inherits from Enemy inherits from Entity, you just give an entity a Position component, a Damage component, and a Flight component. It keeps data cache-friendly, makes the codebase flexible, and scales beautifully when you have thousands of entities.
Example
Unity's DOTS (Data-Oriented Technology Stack) is built around ECS principles and enabled games like Warhammer 40,000: Space Marine 2 to render massive hordes of enemies with smooth performance by keeping data tightly packed in memory.
Why it matters
ECS solves the classic problem of game code turning into an unmaintainable inheritance nightmare. It also unlocks serious performance gains on modern hardware by being cache-friendly, which matters when you are simulating thousands of entities every frame.
Related concepts