Writing JavaScript Statements

A JavaScript program consists of a series of "instructions" that the web browser "executes".

 These instructions are known as statements.

JavaScript statements consist of:

• Values
• Operators
• Expressions
• Keywords
• Comments

Example: Instruct the browser to display "WebmasterMaze." inside an HTML element with the id="statement".

document.getElementById("statement").innerHTML = "WebmasterMaze"; 

• Most JavaScript programs consist of multiple statements.
• These statements are executed sequentially, in the exact order they are written.
• Semicolons are used to separate JavaScript statements.

More Examples: 

<p id="let"></p>

<script>
let a, b, c;    // Statement 1
a = 5;          // Statement 2
b = 6;          // Statement 3
c = a + b;      // Statement 4
document.getElementById("let").innerHTML = "The value of c is " + c + ". ";
</script>

<!-- Output: The value of c is 11. -->

Multiple statements can be written on a single line if separated by semicolons.

a = 5; b = 6; c = a + b;

On the web, you may come across examples that omit semicolons. While it’s not strictly necessary to end statements with a semicolon, it is strongly recommended for better code clarity and reliability.

A good practice is to include spaces around operators (such as =, +, -, *, /) for better readability.

let c = a + b;

JavaScript Keywords

JavaScript statements typically begin with a keyword that specifies the action to be performed.

Below is a list of some of the commonly used keywords.

var - Declares a variable.
let - Declares a block-scoped variable.
const - Declares a block-scoped constant.
if - Defines a block of statements to be executed based on a condition.
switch - Defines a block of statements to be executed in different cases.
for - Defines a loop that repeats a block of statements.
function - Declares a function.
return - Exits a function and optionally returns a value.
try - Implements error handling within a block of statements.