An informal letter is personal.It is written to people we know well.Everything can be included in an informal letter because we can say anything to iur friends.However,there is still a framework to follow.
Organization
____________________________________________________________________________
3rd March,2008
Dear Henry,
(Salutation)
How are you?...
(opening)
I.....
(Body paragraphs)
Write back when you have time.
(Ending)
Best wishes,
(Complimentary close)