4. 請依照高級中學入學新生既有的先備知識來解釋下列名詞或概念，並舉實例說明該技術的實際應用或其未來發展： RFID (Radio Frequency Identification) NFC (Near-Field Communication) UWB (Ultra-Wideband) 5G (5th Generation Wireless Systems) IoT (Internet of Things)