We write our letters from left to right, but we write our numbers from right to left.
When we write the number 100, we write the digits 1, 0, 0 from left to right, but that’s not what I mean.
When we add up a series of numbers, we align them right shifted so that all the positions with the same value are lined up in a row. In order to make that work, we effectively write the numbers from right to left.
Wouldn’t it make more sense to write the least significant digit first, so 100 would be written 001 so that we could write from left to right and the numbers would still line up correctly. Adding 100 and 2036 for example…
001
6302
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6312