Rails are long, narrow strips of metal or wood that provide a track for trains, trams, or other vehicles to travel on. They are typically laid in pairs, allowing the wheels of the vehicles to roll smoothly along the surface. The design of rails helps to guide the vehicles and maintain stability during movement. In addition to transportation, the term "rails" can also refer to the framework used in construction, such as guardrails or handrails, which provide safety and support. Rails are essential in various industries, ensuring efficient movement and safety in both transportation and structural applications.