There are presently two major types of Automated Radar Terminal System (ARTS) models in use at FAA facilities, ARTS models IIE and IIIE. Current versions of the ARTS are now also referred to as Common ARTS or CARTS due to the common national software. The ARTS IIIE version was designed to support 15 sensors, 10,000 simultaneous tracks, and over 200 displays. ARTS-IIIEs are operational at 8 large TRACONs. ARTS IIE versions were designed to support one or two sensors and up to 22 displays in two different configurations that can process 256 simultaneous tracks per sensor.