[Calabash]

Gee, you can quote from the internet.

Try reading here:

http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Zero.html

And here:

http://en.wikipedia.org/wiki/History_of_the_Hindu-Arabic_numeral_system

[CarrotAndStick]

Read it yourself again. Especially the latter part of the first link.