What are some best practices for creating a calendar using PHP and HTML?

When creating a calendar using PHP and HTML, it is important to properly structure the code to ensure flexibility and maintainability. One best practice is to separate the logic for generating the calendar from the presentation of the calendar. This can be achieved by using functions to generate the calendar data and then using HTML templates to display the calendar.

<?php
// Function to generate calendar data
function generate_calendar($month, $year) {
    // Your calendar generation logic here
}

// Display the calendar using HTML
$month = date('n');
$year = date('Y');
$calendar_data = generate_calendar($month, $year);

echo '<table>';
echo '<tr><th>Sun</th><th>Mon</th><th>Tue</th><th>Wed</th><th>Thu</th><th>Fri</th><th>Sat</th></tr>';
foreach ($calendar_data as $week) {
    echo '<tr>';
    foreach ($week as $day) {
        echo '<td>' . $day . '</td>';
    }
    echo '</tr>';
}
echo '</table>';
?>