Using aliases, you can make scripts from the same directory process requests to multiple addresses simultaneously.
Important points:
By default, for the added site, its alias with www is also added.
Only those sites that are not listed in the section "My sites". If you want to add an alias using an existing name, you will need to remove this website or subdomain.
If a domain is added as an alias, which can be accessed both with www and without, then you need to add both variants of the name - with www and without.