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JavaScript Comments

JavaScript comments are used to add explanatory notes or to temporarily disable parts of the code without removing them. Comments can make the code more readable and easier to understand for others (or even yourself) when revisiting the code at a later time. There are two types of comments in JavaScript: single-line comments and multi-line comments.

  1. Single-line comments:

Single-line comments begin with two forward slashes (`//`). Any text following the slashes on the same line is considered a comment and is ignored by the JavaScript engine. For example:

// This is a single-line comment
var x = 10; // Declare a variable and assign the value 10

In this example, the first line is a single-line comment, and the second line includes a single-line comment after the code. Both comments are ignored by the JavaScript engine.

  1. Multi-line comments:

Multi-line comments start with a forward slash followed by an asterisk (`/*`) and end with an asterisk followed by a forward slash (`*/`). Everything between these delimiters is considered a comment and is ignored by the JavaScript engine. Multi-line comments can span multiple lines, as shown in this example:

/* This is a multi-line comment
   that spans multiple lines */
var x = 10;
var y = 20;

In this example, the first two lines are a multi-line comment, which is ignored by the JavaScript engine.

It's important to note that comments should not include sensitive information, such as passwords or API keys, as they can still be viewed by anyone who has access to the source code.

To summarize, JavaScript comments help make the code more readable and can be used to add explanatory notes or to temporarily disable code. Single-line comments begin with `//`, while multi-line comments start with `/*` and end with `*/`. Use comments judiciously to improve the clarity and maintainability of your code.

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