In any form, the difference is -9 hundredths.
The hundredths place is the second to the right of the decimal point.
0.01 . . . . one hundredth
0.10 . . . . ten hundredths (also known as one tenth)
In ten hundredths, the 1 digit is moved one place to the left, indicating its value is 10 times its value in 0.01.
The difference is 0.01 -0.10 = -0.09, negative nine hundredths.