type	description	example
INT	4 byte signed integer i.e. 32 bits ( 232 values can be stored)
BIGINT	8 byte signed integer i.e. 64 bits (264 values can be stored)	ID
CHAR	fixed length string data type, so any remaining space in the field is padded with blanks. CHAR(100) field (or variable) takes up 100 bytes on disk, regardless of the string it holds.
VARCHAR	variable length string data type, so it holds only the characters you assign to it.