Conditional Statements

In JavaScript, conditional statements 
let your code make decisions based on 
whether something is true or false. 
The main ones are
 if, else, 
else if, 
switch, and 
the ternary operator 
? :

1) if statement:

Use if when you want code to run only if a condition is true

let age = 20;

if (age >= 18) {
  console.log("You are an adult");
}

Here, the message prints only when age >= 18 is true

2) if...else:

Use else when you want one block for true and another for false.

let age = 16;

if (age >= 18) {
  console.log("You are an adult");
} else {
  console.log("You are a minor");
}

If the condition is false, the else block runs instead

Flow Chart

3) if...else if...else:

Use else if when you have multiple conditions to check in order

let marks = 72;

if (marks >= 90) {
  console.log("Grade A");
} else if (marks >= 75) {
  console.log("Grade B");
} else if (marks >= 60) {
  console.log("Grade C");
} else {
  console.log("Not Pass");
}

JavaScript checks each condition from top to bottom and runs the first matching block

Flow Chart:

4) switch:

Use switch when one value can match many different cases

let day = "Monday";

switch (day) {
  case "Monday":
    console.log("Start of the week");
    break;
  case "Friday":
    console.log("Weekend soon");
    break;
  default:
    console.log("Normal day");
}

switch is useful when you compare the same variable against several possible values

5) Ternary operator:

The ternary operator is a short form

let age = 19;
let status = age >= 18 ? "Adult" : "Minor";

console.log(status);

It follows this pattern: condition ? expression1 : expression2

Simple rule:

• Use if for one condition

• Use if...else for two outcomes

• Use else if for multiple conditions

• Use switch for many fixed values

• Use ternary for short, simple decisions

Reference:

• https://www.w3schools.com/js/js_if_else.asp

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/if...else

• https://www.javascript.com/learn/conditionals

• https://dev.to/ebereplenty/javascript-conditional-statements-explained-for-beginners-3k5g

Comments

[Jon Randy 🎖️]

The conditional (ternary) operator is not a shorthand for the if statement. It's an operator, not a statement. It forms part of an expression, and is not a control flow statement.

It will evaluate one of two operands based on the truthiness of the first operand. It cannot run other statements or blocks of statements like if and other control flow statements can.

It's similar, but certainly not shorthand for an if/else.

[Raja B]

Spot on! Thank you for the excellent clarification. You are absolutely right—the conditional operator evaluates an expression and returns a value, whereas if/else is a control flow statement that executes blocks of code. I appreciate you pointing out this technical distinction, and I'll update the post to reflect this accurately. Thanks for reading!