The BLOB Type
A BLOB is a binary large object that can hold a variable amount of data. The four BLOB types are TINYBLOB, BLOB, MEDIUMBLOB, and LONGBLOB. These differ only in the maximum length of the values they can hold. The four BLOB types and have the same maximum lengths and storage requirements.
BLOB values are treated as binary strings (byte strings). They have no character set, and sorting and comparison are based on the numeric values of the bytes in column values. TEXT values are treated as non-binary strings (character strings). They have a character set, and values are sorted and compared based on the collation of the character set.