Why would an index page have an extension of php instead of html?
All browser will read html. PHP is needed if you want to create an include file or link to a database. An include file is used if you want to display the same information on multiple pages and only update it once. An html file extension cannot support php code.
What tags are used for tables?
These are the tags used to create a table: table, thead, tr, th tbody, td, and of course all the closing corresponding closing tags.
What languages are used to connect databases to a web site?
HTML and PHP are written with SQL commands to display data stored in a MySQL or Orcale database.