An Interstate is a specific type of federal, high-speed, limited-access highway that crosses state lines, forming part of a national network. A highway is a broader term for any major public, paved road connecting cities and towns. While all Interstates are highways, not all highways are Interstates. Interstate (Interstate Highway System) Definition: Part of the national network authorized by the Federal Highway Administration, designed for high-speed, long-distance travel. Interstate Key Features: Always divided, limited access (no traffic lights or intersections), and usually four or more lanes. Signage: Red, white, and blue shield markers. Purpose: Primarily for interstate commerce and national defense. Highway Definition: Any main, public road connecting cities or regions. Key Features: Can be 2-lane roads or multi-lane freeways. They may include at-grade crossings, traffic lights, and direct access to businesses or residences. Types: Includes state highways, US numbered highways, local, and rural roads. Usage: Used for both long-distance travel and shorter, local trips. Key Differences Scope: Interstates connect states; highways can be solely within one state (intrastate). Access Control: Interstates are always limited-access (no stoplights); highways can have intersections. Funding: Interstates are federally funded/influenced, whereas many highways are state-maintained.