Photoplethysmography (PPG) is a useful diagnostic tool in many clinical and general health monitoring applications because to its non-invasiveness and ease of use. However, great thought must be paid to Human-Computer Interaction (HCI) design in order to fully realize its potential. Enhancing the interface between the user, machine, and service requirements can greatly boost PPG-based systems’ overall performance The skin blood flow using infrared light is estimated by Photoplethysmography (PPG). PPG is a straightforward and inexpensive optical method that may be used to measure variations in blood volume inside the tissue’s microvascular bed. It has various advantages such as non-invasives, in expensive and convenient diagnostic tool. In order to achieve certain performances in quality as well as optimality of the services. Human-computer interaction (HCI) design should produce a match between the user, the device, and the required services. Systolic amplitude, pulse width, pulse area, peak to peak interval, pulse interval, augmentation index, and big artery stiffness index are among the several PPG-related metrics.