Whats the "iteration" field?

I was wondering whats the “iteration” filed in grafana json model? And if and how its connected to the “version” field. I mean this one:
},
“editable”: true,
“fiscalYearStartMonth”: 0,
“gnetId”: null,
“graphTooltip”: 0,
“id”: 416,
“iteration”: 1666103268916,
“links”: ,
“liveNow”: false,
“panels”: [