On a related note, here are some interesting articles.
Do I have to use external CSS and JS files?
Using MySQLi and PDO instead of MySQL_*
It is time to deal with mysql_* functions once and for all. These methods are deprecated and slow. The time to upgrade has long passed yet we still see it everywhere. Since I cannot force every author to update their tutorial and blogs, I decided to write a post to hopefully rank better and provide the essential information to help new comers.