Log explanation

[Mik J]

Hello,
Does anyone knows where I could find an explanation of the different fields in 
the logs
example:34e21ed2c47fe7e3 mta delivery evpid=9765e121d002d97d 
from=<sen...@senderdomain.org> to=<recei...@example.com> rcpt=<-> 
source="10.1.2.2" relay="66.102.1.27 (wb-in-f27.1e100.net)" delay=1s 
result="Ok" stat="250 2.0.0 OK  1698365590 
i10-20020a05600c354a00b003fefa764302si226827wmq.9 - gsmtp"
What is 34e21ed2c47fe7e3
What is 2.0.0and so on
Regards