Post Meta and User Meta — a practical guide to WordPress post meta user meta with clear examples you can reuse in real projects.
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Short description
Use post meta for content attributes and user meta for per-user preferences/state.
User meta
update_user_meta($user_id, 'acme_timezone', 'Asia/Kolkata');
$tz = get_user_meta($user_id, 'acme_timezone', true);