Definition:Babylonian Number System

Definition
The number system as used in the was a positional numeral system where the number base was a combination of decimal (base $10$) and sexagesimal (base $60$).

The characters were written in by a combination of:
 * a thin vertical wedge shape, to indicate the digit $1$
 * a fat horizontal wedge shape, to indicate the digit $10$

arranged in groups to indicate the digits $2$ to $9$ and $20$ to $50$.


 * Babylonian symbols.gif

At $59$ the pattern stops, and the number $60$ is represented by the digit $1$ once again.

Thus these groupings were placed side by side:
 * the rightmost grouping would indicate a number from $1$ to $59$
 * the one to the left of that would indicate a number from $60 \times 1$ to $60 \times 59$

and so on, each grouping further to the left indicating another multiplication by $60$

The fact that they had no symbol to indicate the zero digit means that this was not a true positional numeral system as such.

For informal everyday arithmetic, they used a decimal system which was the decimal part of the full sexagesimal system.