1: DRUPAL 7 AND 8 DIFFERENCE 2: DRUPAL NODES 3: DRUPAL VIEWS 4: DRUPAL CACHE 5: HOW CACHE WORKS 6 HOW TO IMPROVE PERFORMANCE OF DRUPAL 7: CONDITIONAL FILTERS IN IN VIEWS IN DRUPAL 8: PDO IN DRUPAL 9: IMPLODE &EXPLODE DIFFERENCES 10: TRUNCATE & DROP DIFFERENCES 11: HOW TO IMPROVE SPEED OF MYSQL 12: DIFFERENCE BETWEEN GET AND POST 13: Hooks in Drupal. and how does hook work 14: Basic command of GIT 15: Command to commit GIT code. 16: How to optimize MYSQL queries 17: Where are session stored. How to remove session. 18: DIFFERENCE between unlink and unset in PHP 19: What are webservices and How do you consume an API in PHP