A Domain Alias allows multiple domain names to point to the same website.

The best way to explain Domain Aliases would be by using an example.

If www.sampledomain1.com is your main domain and you made www.sampledomain2.com a Domain Alias, when someone typed www.sampledomain2.com in their browser the site from www.sampledomain1.com would be returned.

www.sampledomain1.com and www.sampledomain2.com share the same web root.

Any email sent to your Domain Alias will be automatically forwarded to the parent domain.

You can automatically create, delete and modify domain aliases right from the Server Intellect control panel.

Read more on creating Domain Aliases