At least once in their lifetime, everyone has an idea and wants to own a domain name. But, unfortunately, most of us have bought a fair set of useless ones.
You can use a domain name for numerous things, e.g., pointing at a web host or redirecting to a Facebook or LinkedIn page.
It is also essential for email hosting. Email addresses with IP v4 or, god forbid, v6 are rare beasts. But do you really need a fully functioning mail server to receive mails on your email address with your custom domain name?
Well, it depends. If you want to receive and send mails in a dedicated mailbox, then yes. If your email addresses only serve as forwarders, then no.
We can illustrate a forwarder like this. One could send an email to "firstname.lastname@example.org", but the mail is forwarded to "email@example.com". The forwarder is only a front, and it can not send emails. The mail comes down in mr. bossman's mailbox on Gmail.
When you want to set up email forwarding, you'll need a hosting provider that offers you this feature (alongside the complete email hosting package). Cloudflare is now beta-testing Email Routing, so you don't need an external partner/hosting anymore!
It comes down to this: you configure your DNS records in Cloudflare and click "Email Routing", and Cloudflare provides the required MX and TXT (DKIM, SPF) records for you. From there, the UI explains itself.
And even better, it's a free feature on top of free DNS management in Cloudflare. So from now on, there's no excuse anymore to accept the "firstname.lastname@example.org" variants in professional communication.
More info can be found here