Macro clarification needed

[Alex Regan]

Hi,

I'm using amavisd-new-2.9.1 with spamassassin and fedora20.

Can someone describe to me under what circumstances you would use the 
built-in macros available with amavisd? Is it only for the custom report 
files included from the main config?

I've read README.customize, and I've experimented with building a custom 
config file to create custom log entries, but are there other purposes?

I've always thought they were variables or functions, not macros.

Does spamassassin use them?

Thanks,
Alex