A database is a storage place for information. Usually the information is organized into a series of related categories, where it is stored in an orderly fashion, and can be modified, updated, searched for, retrieved and/or deleted as often as necessary.
MYSQL was once the most popular open source database management system. It was free, and earned a reputation for reliability and ease of use. Nowadays, MariaDB is the open source variation of MYSQL, but for now we'll continue to call it MYSQL rather than getting into the long and complicated history.
Do you ever visit Youtube, Wikipedia, Flickr or Facebook? Have you ever considered how that these gigantic websites manage all of their data, users, etc.? These, and many thousands of other websites make use of massive databases.
Databases are made up of one or more tables of organized data that can be linked together. If you are familiar with Excel/Openoffice spreadsheets or HTML tables, where rows of data are labeled at the top of each column, then you will already have the database-concept half-mastered. If not, stick with us, and we'll explain!
MySQL is officially pronounced "my-ess-cue-el", but is sometimes called "my sequel" or other variations.