Scientific notation is the expression of a number 
in the form 
, where
 |
(1)
|
is the floor of the base-10 logarithm of 
(the "order of magnitude"), and
 |
(2)
|
is a real number satisfying 
. For example, in scientific notation, the number
has order of magnitude
 |
(3)
|
so 
would be written 
.
The special case of 0 does not have a unique representation in scientific notation,
i.e., 
.
Engineering notation is a version of scientific notation in which the powers of ten must be multiples of three. One noted disadvantage of writing numbers in engineering notation is that the significant digits are often difficult to recognize.
