GMT (Greenwich Mean Time) and UTC are frequently treated as the same, but they are not identical concepts. GMT is a time zone historically tied to Greenwich, London. UTC is a global time standard maintained using highly accurate atomic clocks.
As technology advanced, the need for a precise and stable standard increased. UTC is designed for accuracy and consistency in global systems. It does not rely on astronomical observations and does not change for daylight saving time.
In everyday conversation, many people use “GMT” to mean “the world’s reference time.” In most contexts, the displayed time value matches UTC. However, UTC is the correct standard for computing and global coordination.
For international scheduling, software logs, and global communication, prefer UTC. Use local time zones (e.g., Europe/London) when you need region-specific daylight saving rules.