The High Frequency (HF) band is the frequency range from 3 to 30 MHz. RFID systems that operate in this frequency band are called High Frequency (HF) RFID Systems. HF RFID tags/readers usually operate at frequencies from 1.75 MHz to 13.56 MHz. NFC (Near Field Communications) is a sub-set of RFID and also operates in the high frequency (HF) band.
HF RFID tags are based on inductive coupling technology which means that the RFID reader induces a current in the RFID tag which then powers the RFID tag and sends out some basic identification information to the RFID reader. These tags are usually passive and do not require a power source or battery. They have anti-collision capabilities that allow a single reader to read multiple tags simultaneously. The range of these systems is usually under 1 meter ( larger than LF).