This document discusses wearable biosensors and focuses on ring sensors and smart shirts. It describes ring sensors as pulse oximetry sensors shaped like rings that can continuously monitor heart rate and oxygen levels. Smart shirts are described as optimal for sensing, monitoring, and processing vital signs. The document outlines the advantages and disadvantages of both, such as continuous monitoring but high initial costs. It concludes by discussing future trends in wearable biosensors including their potential use in preventing road accidents.