As you move to the left, each place is 10 of the place before.
10 is ten ones.
100 is ten tens.
1000 is 10 hundreds.
Etc.
Going the other way, to the right, the opposite is true.
One is 1/10 of 10.
The same goes on the right of the decimal, where the places are < 1.
1 is ten tenths.
0.1 is 10 hundredths.
Etc.
Going right, each place is 1/10 of the place before it.
If 10 is ten ones, then 1 is 1/10 of 10.
0.1 is 1/10 of 1.
0.01 is 1/10 of 0.1.
Etc.