Introduction to PHP

PHP (Hypertext Preprocessor) is a widely-used, open-source scripting language primarily designed for web development. It can be embedded into HTML and is particularly suited for creating dynamic web pages.

Key Concepts

What is PHP?

• Server-side Scripting Language: PHP runs on the server, generating HTML that is sent to the client's web browser.
• Open Source: Free to use and modify, making it accessible for developers.

Features of PHP

• Cross-Platform: Works on various operating systems like Windows, Linux, and macOS.
• Database Integration: Easily connects to databases like MySQL, PostgreSQL, and SQLite.
• Supports Various Protocols: Can interact with protocols like HTTP, FTP, and more.
• Extensive Documentation: Well-documented, making it easier for beginners to learn.

Basic Syntax

PHP Tags

PHP code is enclosed in <?php ... ?> tags.

Example:

<?php
echo "Hello, World!";
?>

Variables

Variables in PHP start with a $ sign followed by the variable name.

Example:

$name = "Alice";
echo $name; // Outputs: Alice

Data Types

PHP supports various data types:

• String: Textual data.
• Integer: Whole numbers.
• Float: Decimal numbers.
• Boolean: True or false values.
• Array: A collection of values.
• Object: An instance of a class.

Control Structures

If-Else Statements: Used for conditional execution.

Example:

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

Loops: For repeating actions.

• For Loop
• While Loop

Example:

for ($i = 0; $i < 5; $i++) {
    echo $i; // Outputs: 0 1 2 3 4
}

Conclusion

PHP is an essential tool for web developers looking to create dynamic and interactive websites. With its ease of use and vast community support, beginners can quickly get started and build robust applications.

Next Steps

• Explore more advanced topics like functions, sessions, and file handling.
• Practice by creating simple web applications to solidify your understanding.