Purpose: They are meant for users to take short "power naps," which research suggests can reduce fatigue, boost energy, improve focus, and enhance productivity.

Locations: They have become popular in various environments, including:

• Corporate offices (to help employees refresh)

• Hospitals and universities

• Airports (for travelers with long layovers)

• Public spaces (sometimes in dedicated nap cafes)

Features: They sometimes incorporate technology or ambient features to aid sleep and relaxation