Install, Syntax & Comments

Install PHP — local setup

Install XAMPP (Windows/Mac/Linux) or use Homebrew: brew install php. Start Apache and MySQL from the XAMPP control panel.

Save files in htdocs (e.g. htdocs/knowvora/index.php) and visit http://localhost/knowvora/index.php.

Real-life example: Installing PHP is like setting up a workshop. XAMPP gives you the tools (PHP, Apache, MySQL) on one workbench.

• Check version: php -v in terminal
• Built-in server: php -S localhost:8000
• Use VS Code with PHP Intelephense extension

<?php
// Save as index.php and open via localhost
phpinfo(); // Shows PHP version and modules — remove in production!
?>

PHP Syntax

PHP scripts start with <?php and end with ?>. Statements end with a semicolon (;). PHP is not case-sensitive for keywords but is case-sensitive for variables.

Real-life example: Semicolons are like periods at the end of sentences. Without them, PHP gets confused about where one instruction ends.

<?php
// PHP block must start with <?php
echo "Hello, Rishtaara!"; // semicolon required

// Wrong: echo "Hi" (missing semicolon)
?>

Comments

Use // for single-line comments and /* ... */ for multi-line blocks. Comments help humans; PHP ignores them.

Real-life example: Comments are pencil notes in your notebook margin — they remind you why you wrote code, but the teacher skips them.

<?php
// This line is a comment
$course = "PHP Fundamentals"; // inline comment

/*
  Multi-line comment
  for longer explanations
*/
echo $course;
?>