BLOB is large binary object which can have a variable amount of data. Below are the some of very important aspects of BLOB.
(1)BLOB is the family of column type intended as high-capacity binary storage.
(2)Actually BLOB column is of 4 types
(i)TINYBLOB
(ii)BLOB
(iii)MEDIUMBLOB
(iv)LONGBLOB
(3)Four of above BLOB types are similar the only difference is the amount of information data each can store.