The conversion path is the journey the prospect take in becoming a new customer. In the digital marketing world, it looks like this:
Ad Campaign of online advertisements (Banner ads, Ads, pay per click images)
On site movement to a conversion funnel (similar to e-commerce type shopping experience). The middle of the funnel is a form or sell sheet to acquire information about the prospect.
The end of the funnel is the open and then closing the sale with the customer.