This document discusses how to connect to a MySQL database using the mysql binary from the command line and using PHP scripts. It provides an example of connecting to MySQL from the command line using the mysql command and authenticating with username and password. It also discusses the mysql_connect() and mysql_close() PHP functions for opening and closing connections to a MySQL database from within a PHP script, including their syntax and parameters. An example PHP script is given that demonstrates connecting to a MySQL server using these functions.