Flatmates are individuals who share a living space, typically in a house or apartment, to reduce living costs and share responsibilities. They often split rent, utilities, and household chores, making it a practical arrangement for students, young professionals, or anyone looking to save money. Living with flatmates can foster friendships and provide social support, but it also requires good communication and compromise. Establishing house rules and respecting each other's privacy are essential for maintaining a harmonious living environment.