Single-line comments begin with two forward-slashes (//).
Multiline comments start with a forward-slash followed by an asterisk (/*) and end with an asterisk followed by a forward-slash (*/).
Examples
4 + 6 // this is a comment
Multiline comments
a=6
/* this is a
multiline comment */
a^2
Nested multiline comments
a=16
/*
this is the start of the first multiline comment
/* this is the second,
nested multiline comment */
this is the end of the first multiline comment
*/
sqrt(a)