For newcomers to Web, I'll give a brief definition of a domain name.
Your domain name is same as "www.yoursitename.com". It's also known as your URL or Website Address.
For example, www.webmastercourse.com is my site's domain name or my web address.
The domain name must be registered and approved before you can call it your own. The reason it works this way is because two websites having same domain name cannot reside online at same time. If someone types in www.webmastercourse.com, he/she will go to my website and no one else's.
Registering your domain name and awaiting approval gives registration company opportunity to check with every other company around world to be sure no one else has already applied for your domain name "first."
It normally takes 2 to 3 days to receive confirmation of your domain name.
If you haven't registered your own domain name yet, please take following tips into consideration before doing so.
Your domain name can affect number of repeat visitors to your website.
1. Visitors will only remember your domain name for a future visit if it is easy to remember.
Which of two domain names below would you more likely remember?
http://www.webmastercourse.com/ or http://www.web-designer-training-course-part-1-learn.com/
Probably first one. The shorter better. Visitors will see domain name, remember it, and hopefully visit again in future if domain name is simple and to point.