Many professionals use the Product Manager and Project Manager roles/terms interchangeably. Even though Both the roles often work together on the same business case or initiative, they have distinct roles and responsibilities.

A business case undertaken will lead to creating a product or service or result meaning, creating a product that can be a tangible good, service, or system that solves customers’ problems and satisfies their needs, thus creating value. [ITIL4] 

Web Site development is Product and the creation of web site is achieved via development undertaken via executing Project. A project is a process of creating a product or service. It is a collection of tasks with a timeline and a defined outcome. Projects revolve around a product, it is temporary, and their purpose is to develop and deliver a product.

In order to facilitate the creation or delivery of Product/Result/Service, the Product Manager – is responsible for the vision, strategy, and product goal. They look after the “what” and “why” part of the product. For example, what will the end-product look like? What problem will it solve? While the Project Manager focuses on “How” & “When” of the Product delivery, how will the product be delivered? When will it be delivered?

“A product manager concentrates on product development and releases, while a project manager coordinates, supervises, and oversees project which enables to deliver desired Product/Result/Service.” The product manager deals with the “what” and “why” of the product. The project manager deals with the “how,” “when,” “where,” and “who.”