GMT? GMT? What??

World Time Zones, as found on the CIA WWW Page

In order to reduce the amount of confusion, a standardized time-of-day was adopted by the world meteorological community (and others). Originally, this was Greenwhich Mean Time (GMT), but the atomic-clock boyees insisted that GMT wasn't right. They're splitting hairs over a few seconds, at best. This newer standard is refered to as UTC (Universal Time Coordinated - translated from the French, which explains why it's not UCT). GMT is often abbreviated as Z (aka Zulu) time. I've always assumed that this is because Greenwhich, England sits on the Prime Meridian (Zero degrees east longitude), and makes for a quicker/easier transmission for a manual typist.

Ok, that's the apochryphal version. But what does that mean to you, the average user who gets confused by the Daylight Savings two-step? Well, it's fairly straight forward:

1800 GMT is nearly the same as 1800 UTC, is identical to 1800 Z. And on the East Coast of the United States, that translates to 1300 EST/1400 EDT. Adjust accordingly to your time zone.

If you're curious, the US Naval Observatory is the offical time source in the United States.