Arrays in PHP are used to store multiple values in a single variable instead of creating separate variables.

👉 Example:

$fruits = ["Apple", "Banana", "Mango"];

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🔹 1. Indexed Arrays

These arrays use numeric indexes (0, 1, 2…)

✅ Example:

$colors = ["Red", "Green", "Blue"];echo $colors[0]; // Red
echo $colors[1]; // Green

✅ Using loop:

for ($i = 0; $i < count($colors); $i++) {
    echo $colors[$i] . "<br>";
}

👉 Best for: lists of items

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🔹 2. Associative Arrays

These arrays use named keys instead of numbers

✅ Example:

$student = [
    "name" => "Aditya",
    "age" => 22,
    "course" => "BCA"
];echo $student["name"]; // Aditya

✅ Loop:

foreach ($student as $key => $value) {
    echo "$key: $value <br>";
}

👉 Best for: structured data (like objects)

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🔹 3. Multidimensional Arrays

Arrays inside arrays (used for complex data)

✅ Example:

$students = [
    ["Aditya", 22, "BCA"],
    ["Rahul", 21, "BSc"],
    ["Neha", 23, "MCA"]
];echo $students[0][0]; // Aditya
echo $students[1][2]; // BSc

✅ Loop:

foreach ($students as $student) {
    echo $student[0] . " - " . $student[2] . "<br>";
}

👉 Best for: tables / database-like data

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🔹 4. Important Array Functions

✅ 1. sort() → Sort values (ascending)

$numbers = [3, 1, 5, 2];
sort($numbers);
print_r($numbers);

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✅ 2. rsort() → Descending sort

rsort($numbers);

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✅ 3. asort() → Sort associative array by value

$age = ["Aditya" => 22, "Rahul" => 20];
asort($age);

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✅ 4. ksort() → Sort by key

ksort($age);

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✅ 5. array_merge() → Combine arrays

$a = ["Red", "Blue"];
$b = ["Green", "Yellow"];$result = array_merge($a, $b);
print_r($result);

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✅ 6. array_filter() → Filter values

$numbers = [1, 2, 3, 4, 5];$even = array_filter($numbers, function($n) {
    return $n % 2 == 0;
});print_r($even);

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✅ 7. array_map() → Modify each value

$numbers = [1, 2, 3];$square = array_map(function($n) {
    return $n * $n;
}, $numbers);print_r($square);

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🎯 Summary

Type	Use Case
Indexed Array	Simple lists
Associative Array	Key-value data
Multidimensional Array	Complex/nested data

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💡 Teaching Tip (for your students)

Explain like this:

• Indexed = List 📋
• Associative = Dictionary 📖
• Multidimensional = Table 📊