A CNAME record associates one domain name to another domain name.
Some reasons of doing so are:
- Having multiple domain names pointing to the same website: for example “jeremyandersonlin.com” and “jlin.com”.
- Using subdomains with my own web applications: if subdomain’s web applications are on the same computer as the main web application, subdomain’s requests must also be sent to the same computer. In this case one can create a CNAME record that associates subdomains to the main domain.
- CNAME, www, @: point “www.example.com” to main domain “example.com”.
- CNAME, blog, @: point subdomain “blog.example.com” to main domain “example.com”