Databases are a tool to persist data that you intend to refer to regularly and need to keep for a long time.
PHP uses extensions to interact with a range of databases. For example, to interact with the MySQL database, you can use the functions provided by the mysqli extension.
Note
There is an “i” at the end of mysqli. This is the replacement for the now deprecated mysql extension. Features like “prepared statements” are only available with the new extension.
PHP also offers abstraction layers that provide an application layer between your code and the database. We'll be looking ...
