difference between "task" and "job"?

[Tomohiro KUBOTA <debian@tmail.plala.or.jp>]

Hi,

I am now revieweing a Japanese translation of Debian web page,
devel/join/nm-step4.

The page has words like "task" and "job".  In Japanese language,
there are no distinct words for these two words.  Thus, I don't
understand the difference between them.

Are these words used just by chance?  (In English class, Japanese
people learn that English speakers like to use different words
to mention one object when the object is mentioned multiple times.)
Or, does the difference between them have some meaning?

I guess "task" means four fields (or classification) of "jobs":

 - Package Management 
 - Documentation 
 - Debugging and Testing 
 - Infrastructure 

However, I don't understand what "Alternative demonstration tasks"
means.  Does it mean jobs which cannot be classified into the four
fields and demonstration jobs to prove that the applicant can do it?
Or, just some jobs which _can be_ classified into the four fields
but the applicant wants to prove his/her skill in different way?

---
Tomohiro KUBOTA <kubota@debian.org>
http://www.debian.or.jp/~kubota/