This document discusses wearable biosensors and summarizes key information about smart shirts. It describes how biosensors work by converting biological responses into electrical signals using biological, physiochemical and signal processing components. It provides examples of wearable biosensors like smart shirts and ring sensors that can continuously monitor vital signs. Smart shirts offer advantages like easy use and remote health monitoring but also have disadvantages like high initial costs and limited battery life. The document discusses applications of smart shirts in areas like medical monitoring, sports performance, and hazardous work environments.