Order creation date on the "get order" endpoint?

In postman collection, I see a ‘get order’ endpoint with query string parameters ‘start_at’ and ‘end_at’. For example:
"{{baseUrl}}/api/{{apiVersion}}/orders?offset=0&limit=10&start_at=2017-04-10&end_at=2017-04-10"
What does the date represent? Is it the order creation date?