What is the purpose of the Jotform?

JotForm is a powerful online application that allows anyone to quickly create custom online forms. Its intuitive drag-and-drop user interface makes form building incredibly simple, and doesn’t require you to write a single line of code. Using JotForm, you can create and publish forms, integrate them into your site, and receive responses by email.

More information about Jotform can be found here;
https://www.jotform.com/faq/

It could be you were filling up a form online, that was using Jotform, thus you were redirected. Hope that helps. Let me know if you have any other concern