There are lots of technology terms that you’ll come across these days and BETA is one of them. Developing software (computer programs) takes time and lots of trial and error. Many times, especially on the internet, developers will create a webpage and put it on the internet before it’s actually done. They do this so the general public can experiment with it and they can collect data to improve it. These “not quite ready for prime time” websites are usually labeled “BETA Version.”
The Museum of Modern Betas is a great website to check out for a list of the most popular Beta version websites in the world. The list is updated every week and includes lots of neat new websites that are currently under development. Here's just a few that you might want to check out:
Flickr - Free photo sharing
FlickrVision - See real-time locations of pictures that are being added to Flickr.
WetPaint - Website that offers free webspace to anyone.
Zillow - Real estate listings and estimated prices throughout the USA.
WuFoo - Use this site for making online forms and surveys.
Like - Shop based on what things look like
Some of these websites display the word "BETA" as part of their logo, some do not. But they're all fairly new ideas that are under development. Sometimes you can even find a website that's in the ALPHA phase of development which is really early on.