origin of zero

What strikes me about this article is that there was so much trouble in making a number that means nothing, and makes me wonder what the process was when they came up with all the numbers. We decide who discovers what when it’s the first one who recorded proof of them discovering it. Mesopotamians discovered zero because they were the first to create and record them discovering it. I don’t think that the person who came up with the idea of zero was the same person discovered it because it could have been thought up a while ago but some one wrote it down and put it to use. I think map makers and sailors probable spread word of zero by traveling to so many places.