Comments

% This is a comment
/* This is a
multi-line comment */

Numbers

42
3.1415

Strings

"This is a string."
"This is a string \
on multiple lines."
"A string with \"quotes\" in it."
"Another string with ""quotes"" in it."

Example

:- dynamic fibo/2.
fibo(0, 1). fibo(1, 1).
fibo(N, F) :-
N >= 2, N1 is N - 1, N2 is N - 2,
fibo(N1, F1), fibo(N2, F2), F is F1 + F2,
assert(fibo(N,F):-!). % assert as first clause