Intrinsic Data Types 

              .data
              value1      WORD      100h
              value2      SDWORD    -40000
              value3      BYTE      'A'
              finalVal    DWORD     ?
MASM defines various intrinsic data types, each of which describes a set of values that can be assigned to variables and expressions of the given type. In the table below, all data types pertain to integers except the last three. The notation “IEEE” refers to standard real number formats published by the IEEE Computer Society.

Type Usage Example
BYTE 8-bit unsigned integer value1 BYTE 'A'
SBYTE 8-bit signed integer Value2 SBYTE -128
WORD 16-bit unsigned intger _value3 WORD 100h
SWORD 16-bit signed integer @value4 SWORD ?
DWORD 32-bit unsigned integer $value5 DWORD 1, 2, 3, 4, 5
SDWORD 32-bit signed integer _6 SDWORD -20d
FWORD 48-bit integer @7 FWORD 0
QWORD 64-bit integer $8 QWORD -100q
TBYTE 80-bit (10-byte) integer _ TBYTE 05E39h
REAL4 32-bit (4-byte) IEEE short real @ REAL4 -1.6
REAL8 64-bit (8-byte) IEEE long real $@ REAL8 1.2E-12
REAL10 80-bit (10-byte) IEEE extended real @_$ REAL 3.2E+1024