The Cloud Flow Designer is a tool to create Flows, configure screens, and define business logic for your Flows without writing a single line of code. Visual Workflow has three different parts, these are as follows:
Design: This allows you to create the Flows using the Flow Designer, which has a drag and drop user interface that allows you to draw the Flow structure and configure how it runs, without writing a single line of code.
Runtime: A Flow user can run the active Flow from a custom button, link, Visualforce page or directly from the Flow URL. If it is autolaunch Flow, then systems can run active Flows through Process Builder or an Apex class.