The information schema in MySQL is a great tool for obtaining just about any type of meta-data about your MySQL server. It is a schema consisting of views that provide just about any information you would want to know about your MySQL installation. For instance, you can find out status and system variables, process listing, database object listing - schemas, tables, triggers, stored procedures and their organization within MySQL, user privileges. .

Originally, people would use SHOW commands to obtain this information. For instance, to see all the schemas (databases) within your MySQL instance:

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| admin              |
| aps                |
| contacts_db        |
| fed                |
| memc               |
| metatalk           |
| myschema           |
| mysql              |
| sakila             |
| syscp              |
| …