The next most important record types are the A and AAAA records, which map a hostname to an IP address. A maps the host to an IPv4 address, whereas an AAAA record maps it to an IPv6 address.
We want to point api.hobnob.social to the server that's running our server (142.93.241.63), so we need to create the following A record:
api IN A 142.93.241.63
We can also direct traffic going to hobnob.social to the same IP address. But instead of writing the full hostname (hobnob.social), we can replace it with the @ symbol:
@ IN A 142.93.241.63
In our records, we can use the @ symbol as a placeholder/substitute for the $ORIGIN parameter.
Since these settings often don't need to be changed, DigitalOcean has set them for us, but not exposed them in the administrative UI.
Many domains also have a catch-all record that directs all traffic not specified with a record to an IP address:
* IN A 142.93.241.63
However, using a catch-all (*) is not a good practice because a malicious party can link to your domain using a sub-domain such as scam.hobnob.social. If we do not have a catch-all record, when Google crawls that link, it will receive an error saying that the host cannot be reached. However, if you have a catch-all record, the request will be directed to your server, and your web server may opt to serve the default server block. This may make scam.hobnob.social the top result when people search for hobnob.social, which is not ideal.