How does sending an email from within Excel work?

I was wondering if this is possible, but also how does Excel know what email template to use that is pre addressed and/or has a default text in Subject field and body of the email.  It does not need to have an attachment, and is more of an alert that a file is done and available for review.  The Subject field usually has todays date in it and I at times put a comment in the template body when an issue prevents the file from being complete.  Curious how others may have approached this in Excel, or is this something that should goto an OutLook area of EE?  -R-