Abstract. The technological advancement in the past three decades has impacted our lives and wellbeing significantly. Different aspects of monitoring our physiological parameters are considered. Wearable sensors are one of its most important areas that have an ongoing trend and have a huge tendency to rise in the future. The wearable sensors are the externally used devices attached to any individual to measure physiological parameters of interest. The range of wearable sensors varies from minuscule to large scaled devices physically fitted to the user operating on wired or wireless terms. Many common diseases affecting large number of people notably gait abnormalities, Parkinson's disease are analysed by the wearable sensors. The use of wearable sensors has got a better prospect with improved technical qualities and a better understanding of the currently used research methodologies. This chapter deals with the overview of the current and past means of wearable sensors with its associated protocols used for communication. It concludes with the ways the currently dealt wearable sensors can be improved in future.