The XT90 is a popular battery connectors commonly used in Electric Vehicle battery backs and other RC or Drone applications. The XT90-S version comes with an in-built load resistor to avoid sparks that generally occur when connecting battery terminals.
USB TYPE-C is a new port designed for high speed data exchange and high power deliver capability. The first thing to realize is that USB TYPE-C is not a new USB standard like USB1.0, USB2.0, USB3.0 and USB3.1.
RS232 connector is a port used for data exchange between equipments. It was designed for data exchange between DTE (Data Terminal Equipment) or PC and DCE (Data Communication Equipment) or MODEM. The need for RS232 came from limitations raised by parallel data exchange.