Figma's own official documentation on Auto Layout: direction, spacing, padding, alignment, the hug/fill/fixed resizing model, nesting, and how it interacts with components and prototypes.
The authoritative, always-current explanation straight from Figma, not a third-party summary that can go stale.
Anyone who uses Auto Layout by trial and error and wants to actually understand the model.
Free, and the single most reliable source since Figma maintains it directly.
Figma's own help-center article on Auto Layout -- direction/flow, spacing, padding, alignment, the hug/fill/fixed resizing model, nesting, and how it interacts with constraints, components, and prototypes.
