Local Time is the time people see on their clocks. Local time is based on the sun's day/night cycle in each of the world's 24 different time zones.
Universal Time (UT) is a measure of world time. It is based on the local time at the Prime Meridian in Greenwich, England (at zero degrees longitude). Universal Time and Greenwich Mean Time (GMT) can be used interchangeably. Universal Time is an international time-keeping standard. We use it to communicate about events that occur at a specific moment. In Universal Time, it is the same time everywhere on Earth.