How can developers ensure that their PHP rewrite rules are search engine friendly and improve SEO?

Developers can ensure that their PHP rewrite rules are search engine friendly and improve SEO by creating clean and descriptive URLs that include relevant keywords, using permanent redirects (301) for any URL changes, and avoiding duplicate content issues by setting canonical URLs. Additionally, developers should regularly check and update their rewrite rules to ensure they are still functioning correctly.

// Example of creating a clean and descriptive URL in PHP
RewriteRule ^products/([a-zA-Z0-9_-]+)$ product.php?slug=$1 [L]