Explanation for post variables being bold?

[parry...@googlemail.com]

I am trying to find out why post variables in the post request tab are
bold. In my implementations for some reason the post body is just one
big string, which I have queried some other people but they don't know
either.

Can you explain what they are specifically, as this might allow me to
fix the broken functionality that I am having at the momment.

Kind Regards
Mr P.