float and real

Approximate number data types for use with floating point numeric data. Floating point data is approximate; not all values in the data type range can be precisely represented.

float[(n)]

Floating point number data from - 1.79E + 308 through 1.79E + 308. n is the number of bits used to store the mantissa of the float number in scientific notation and thus dictates the precision and storage size. n must be a value from 1 through 53.

real

Floating point number data from -3.40E + 38 through 3.40E + 38. Storage size is 4 bytes. In SQL Server, the synonym for real is float(24).