Condenser (or Capacitor) microphones are fantastic for detailed recording work. When using them for vocal recording, think about if you need a pop filter (to stop plosives) or a reflection shield to minimise room noise on recordings and produce a clearer result.
All condenser microphones need a power supply from somewhere, either battery or 48V Phantom Power from a desk or interface.
USB Mics include a digital converter, most dont have conventional XLR sockets, but provide an easy way of recording vocals into your computer. Fantastic for recording speech and voiceovers.