How can browser caching affect the loading of images on a PHP website?

Browser caching can affect the loading of images on a PHP website by storing previously loaded images in the user's browser cache. This can improve loading times for returning visitors as the images don't need to be re-downloaded each time. To ensure that images are cached properly, you can set the caching headers in your PHP code to specify how long the images should be cached for in the browser.

// Set caching headers for images
$expires = 60 * 60 * 24 * 30; // 30 days
header("Cache-Control: max-age=$expires");
header("Expires: " . gmdate("D, d M Y H:i:s", time() + $expires) . " GMT");