What is the difference between duat.com and duats.com?

Question

From what I can tell, they are both sponsored by the FAA, but why have two sites that do the same thing? Do they perform different functions? I had always used duat.com because I thought it was the 'official' one, but duats seems more popular and looks equally official. Which one do you prefer?

www.duat.com

www.duats.com

In addition to these, what other websites do you use to get aviation weather?

I use this one too:

www.aviationweather.gov

Thanks everyone for your answers!

Answer 1

Use duat, it is better than duats in my opinion.  aviationweather is awesome for satellite, radar, metars and tafs, and just quickly checking the weather.   It's also awesome because it has the java tools that let you look at diagrams of airmets, sigmets, convective sigmets, etc. rather than charting them out.   duat is better for in depth briefings and of course, storing record of your briefing.