Comment (JavaScript)

Mon, 01 Jan 0001 00:00:00 +0000

Single Line Comment#

A single line comment starts with // and continues until the end of the line.

// Everything on this line is commented.
console.log("Hello, World!");

You can also write it inline, to the right of your code:

console.log("Hello, World!"); // Everything to the right is commented.

A block comment starts with /* and ends with */. Everything in between is ignored.

/*
This is a block comment.
It can span
multiple lines.
*/
console.log("Hello, World!");

You can also use block comments in a single line or inline:

Mon, 01 Jan 0001 00:00:00 +0000

In JavaScript, you declare a variable using the let keyword, followed by the name, followed by = and the value:

let score = 0;

There is no need to specify a type. JavaScript figures out the type from the value on the right.

Use let when the value may change later. Use const when the value should stay the same: