How to use mail on ubuntu server ?

Hello there

I came across a problem with sending emails to customers.  I have a page for cron jobs, when I open that it should send emails to some customers. it is the response of page "The email could not be sent for an unknown reason".

So, is there any requirement for using that email system on the Ubuntu server? should i install something for use it ?

Thank you

Configure use of an SMTP server for signing and best reliability.