A container divides content into meaningful sections. Just like storage containers help organize a pantry, UI containers help structure and group content.

Containers can hold text, images, or action items. Rigid containers restrict the size or cropping of the elements inside them. Flexible containers grow to fit the size of the content they hold.^[1] That’s how responsive design works: all elements are placed inside containers that adapt to screen size and orientation, ensuring consistency across layouts.