As data type category name implies these are used to store text values. Always make sure you length of your textual data do not exceed maximum lengths.
Type |Value
-----|-----
CHAR( ) |A fixed section from 0 to 255 characters long.
VARCHAR( ) |A variable section from 0 to 255 characters long.
TINYTEXT |A string with a maximum length of 255 characters.
TEXT |A string with a maximum length of 65535 characters.
BLOB |A string with a maximum length of 65535 characters.
MEDIUMTEXT |A string with a maximum length of 16777215 characters.
MEDIUMBLOB |A string with a maximum length of 16777215 characters.
LONGTEXT |A string with a maximum length of 4294967295 characters.
LONGBLOB |A string with a maximum length of 4294967295 characters.