PHP 8.3 is a major update of the PHP language.
It contains many new features, such as explicit typing of class constants, deep-cloning of readonly properties and additions to the randomness functionality. As always it also includes performance improvements, bug fixes, and general cleanup.

PHP 8.0 is now EOL

All Drupal sites should start making sure they work with stronger PHP versions,

Drupal 10.x is best working with PHP 8.0 and higher

It would be best if you started planning to move towards PHP 8.2 or 8.3

Drupal 7 will officially reach its End of Life on 5 January 2025. 

This date marks the 14th anniversary since Drupal 7 was released on 5 January 2011. 

It is recommended to migrate your site as soon as possible.

Drupal is an open-source content management platform supporting a variety of websites ranging from personal weblogs to large community-driven websites.

Drush is a command line shell and Unix scripting interface for Drupal. Drush core ships with lots of useful commands for interacting with code like modules/themes/profiles. Similarly, it runs update.php, executes sql queries and DB migrations, and misc utilities like run cron or clear cache. Drush can be extended by 3rd party commandfiles.