Comments

Comments are arbitrary strings of symbols placed between the delimiters /* and */. The whole sequence is equivalent to a white space. Note that /* */ can be nested. It is useful to comment a block of program with comments in it. Lines beginning with % (no even spaces or tabs before it) are also comment lines.

/* This is a comment */
/* --- Begin of comment ---
        /* This is a nested comment */
--- End of comment --- */
% This is a single-line comment

Comments are not parts of the executable program, but are used by the programmer as a documentation aid.