Comments in JavaScript is a piece of text that is not taken for execution. JavaScript engines ignore the comment text. Comments are purely for adding usability and readability of code.
As the name tells, a Single Line Comment is restricted to one line.
// This is a single line comment
////// Another single line comment //////
Any text that comes between //
and end of the line is ignored by the JavaScript engine.
We can also place a comment by wrapping the text between /*
and */
. This enables having multi-line comment.
/* This is a multiline comment.
It spans three lines.
Oh! I am the third line. */
Since the end of this comment is marked using */
, things will go wrong if we try to nest multiline comment.
/* Parent comment starts
/* Nested comment */
Parent comment continues */
In the above example, the third line is not part of comment and will throw error.