YunoHost comes with a complete mail stack allowing you to host your own email server, and therefore to have your own email addresses in `something@your.domain.tld`.
The mail stack includes a SMTP server (postfix), an IMAP server (Dovecot), an antispam (rspamd) and DKIM configuration.
To interact with the email sever (read and send emails), you can either install a webclient such as Roundcube or Rainloop on your server - or configure a desktop/mobile client as described in [this page](email_configure_client).
Desktop and mobile clients have the advantage of copying your emails to the device, allowing offline viewing and relative protection against possible hardware failures of your server.
Mail aliases and forwards can be configured for each users. For instance, the first user created on the server automatically has an alias `root@the.domain.tld` configured - meaning that an email sent to this adress will end in the inbox of the first user. Automatic forwards may be configured, for instance if an user doesn't want to configure an additional email account and just wants to receive emails from the server on, say, his/her gmail address.
Another feature which few people know about is the use of suffixes beginning with "+". For example, emails sent to `johndoe+booking@votre.domaine.tld` will land in John Doe's mailbox. It is a practical technique for example to provide an e-mail address to a website, then easily sort (via automatic filters) the mail coming from this website.
If your server becomes unavailable, emails sent to your server will stay in a pending queue on the sender's side for as long as ~5 days. The sender's hoster will regularly try to resend the email, until it drops it if it was unable to send it.