The TABLES table contains all the information about the table, such as which database belongs to TABLE_SCHEMA, the number of rows (TABLE_ROWS), ENGINE, DATA_LENGTH, INDEX_LENGTH, and DATA_FREE:
mysql> DESC INFORMATION_SCHEMA.TABLES;+-----------------+--------------------------------------------------------------------+------+-----+-------------------+-----------------------------+| Field | Type | Null | Key | Default | Extra |+-----------------+--------------------------------------------------------------------+------+-----+-------------------+-----------------------------+| TABLE_CATALOG | varchar(64) | NO | | NULL | || TABLE_SCHEMA | varchar(64) | NO | | NULL | || TABLE_NAME | varchar(64) | NO | | NULL | || TABLE_TYPE | enum('BASE ...