How to output a curly brace, which is interpreted only as a character?

Question

Possible Duplicate:
Writing { and } to a file with LaTeX

I want to output a curly brace, which will not be interpreted as a group delimiter. My attempt does not work:

\def\aa{\string}}

I want that calling \aa will output }.

EDIT As egreg mentionned, my aim is to have a brace that can be later on written into a file. The proposed solution \{ outputs correctly a brace, but attempting to write it in a file fails :

\newwrite\tempfile
\immediate\openout\tempfile="nico.txt"
\def\aa{\{}
\immediate\write\tempfile{blabla blabla \a blabla}

Answer 1

Just use \}

This is probably a duplicate question.

Edit: I should also say; putting a backslash \ before nearly any special character in TeX will cause LaTeX to treat it as non-special (and vice versa).

You can either use \} directly, or just put it inside the macro definition:

\def\aa{\}}