Does it make games? o.0 Well... it CAN. If you know what you're doing. But that's not the only thing it's used for (it's not even really it's primary use).
MySQL is a widely-used database software. It stores data, like username and passwords, and other content used on websites. PHP is a server-side scripting language. It interacts with a MySQL database (or other types of databases) and processes the information it finds there into something more user friendly.
For example, say you had a MySQL database that contained several news articles, and a user on your website wanted a specific one of those articles. PHP would ask MySQL for all of the records related to that article, process them, and spit them out on the user's screen in a format they could read.
