[Orgmode] Embedded code

[Ido Magal]

Hello,

Is it possible to put code in a document such that it gets evaluated
when the document is opened?  For example, I'd like to have a
link-back section in each note. I'm aware of babel but I neither
understand how to make it auto-evaluate on open nor do i know if
making it compact ( and avoid separate code and result blocks ) is
possible.

Thanks in advance.