GMT
GMT (Greenwich Mean Time) is a time standard based on the mean solar time at the Royal Observatory in Greenwich, London, historically used as the prime meridian (0° longitude). It served as the world's time standard before being largely replaced by Coordinated Universal Time (UTC) in 1972, though the terms are often used interchangeably in casual contexts. GMT does not account for leap seconds and is tied to Earth's rotation, making it less precise than atomic time-based standards.
Developers should understand GMT when working with time-sensitive applications, such as scheduling systems, global event coordination, or legacy systems that still reference it. It's crucial for handling time zone conversions, especially in international software, databases storing timestamps, or APIs that require time standardization, though UTC is now the preferred standard for most technical implementations.