Alias term explained

Alias means synonym an additional domain name that will link to the same website. Alias is the domain the website in addition to the existing name.

Examples of aliases could be: 

directory.google.com and dir.google.com

or most often it is the domain without www and with www prefix: 

www.seoheronews.com and seoheronews.com

As aliases refer to the same website, ip address and whois are the same.