QFD is an approach for integrating the voice of the customer into product, service or process development and improvement. The main purpose is to consider all important customer requirements. Understanding customers is the central feature of QFD.
The House of Quality is quality tool or matrix for integrating customer needs with technical design and process requirements. Once customer requirements are defined the must be translated into technical terms. For example in manufacturing customer requirements should be translated into specification for materials, process, equipment, dimensions, etc.
The House of Quality lists the customer requirements on the left side and technical requirements near the top while the important relationships with the level of importance are shown in Relationship Matrix in the center of the tool.