There are eight different types of herpes viruses (and chances are, every single person you know has had at least one of them):

HSV-1 (or HHV1): Your garden-variety oral herpes or cold sores.

HSV-2 (or HHV2): Genital herpes.

HHV3 (or varicella-zoster virus): Chicken pox, and later, shingles.

HHV4 (or Epstein-Barr virus): Causes mononucleosis.

HHV5 (or CMV, Cytomegalovirus): Also causes mononucleosis. Mostly mild symptoms in healthy people, but can wreak havoc on those with compromised immune systems, such as HIV patients.

HHV6: Causes Roseola and also thought to be a cause of chronic fatigue syndrome.

HHV7: Also Causes Roseola. It is believed that virtually everyone over the age of two has been exposed to both HHV6 and HHV7.

HHV8: Recently discovered virus that is linked to Kaposi's Sarcoma (a type of tumour) and lymphomas. More common in HIV patients because their immune system is no longer able to fight the virus that causes the tumours. It's actually a postive discovery, because doctors may be able to more effectively fight the virus itself than the tumours it causes.

Note: HSV stands for Herpes Simplex Virus and HHV stands for Human Herpes Virus.