Scientific notation is used to express very large or very small numbers. A number in scientific notation is written as the product of a number (integer or decimal) and a power of 10. The number has one digit to the left of the decimal point. The power of ten indicates how many places the decimal point was moved.

The decimal number 0.00000065 written in scientific notation would be 6.5x10^-7 because the decimal point was moved 7 places to the right to form the number 6.5. It is equivalent to 6.5*0.1*0.1*0.1*0.1*0.1*0.1*0.1

A decimal number smaller than 1 can be converted to scientific notation by decreasing the power of ten by one for each place the decimal point is moved to the right.

Scientific notation numbers may be written in different forms. The number 6.5x10^-7 could also be written as 6.5e-7.