[Hampshire] Sending emails

Just wanted to get my head straight.
do any of you use postfix or you stick with sendmail?

over the years I have installed redhat /now fedora. I use mutt and
fetchmail only configured those.
so being bored and read about postfix more secure than sendmail I
thought I have a go.
Could not get my head round it . I did not know postfix could affect
fetchmail. so when I removed postfix and installed sendmail
fetchmail does not work

determend to sort it out what settings do I need to change on postfix?
I have spent hours on mutt to my liking and on fetchmail I only have
to
enter my pop settings/ password etc.
Don't really want to read miles and miles of text when you only want
to send emails

Fintan