PHP Basics: Understanding if and else

What is an if statement?

if lets you make decisions in your code.

Basic Structure

<?php
if (condition) {
    // do this if true
} else {
    // do this if false
}
?>

Example

<?php
$age = 20;

if ($age >= 18) {
    echo "You’re old enough to vote!";
} else {
    echo "Sorry, come back when you're older.";
}
?>

Output: You’re old enough to vote!

Using else if

Need more than just yes or no? Use elseif to check extra conditions:

<?php
$score = 85;

if ($score >= 90) {
    echo "You got an A!";
} elseif ($score >= 80) {
    echo "You got a B!";
} else {
    echo "Keep trying!";
}
?>

Output: You got a B!

Comparison Operators You’ll Use

Common Mistakes

• ❌ Using = instead of ==
= sets a value, == compares it!
  ✅ Correct: if ($x == 5)

• ❌ Missing curly braces {}
  Always use them for clarity, even for one-liners!

Real-World Example (with HTML)

<?php
$isLoggedIn = false;

if ($isLoggedIn) {
    echo "<p>Welcome back!</p>";
} else {
    echo "<p>Please log in.</p>";
}
?>

Output: 

Please log in.

Practice if/else with different values and conditions. It’s one of the most important building blocks in PHP!