Consistently when I have looked at Ubuntu installations, upon login, I have seen a notification like "You have new mail"
I am interested in how this works, how to both send and receive mail.
The accepted answer to this question says that it should be as easy as typing
mail -s to send mail.
However, when I try that on
16.04 I get the message
The program 'mail' is currently not installed. To run 'mail' please ask your administrator to install the package 'mailutils'
Am I correct that I need to install
mailutils to send both local (i.e. to another user) and external mail messages?
This looks like it also involves Postfix, do I need Postfix to use the local mail option?
Lastly, I asked here about programs such as
cron that send a mail message to a user at certain points in time - if
mailutils is not installed, is
cron able to send any mail messages at all?