HPV is the human papilloma virus. There are over 100 strains that infect the genital area. This is the same virus that causes warts elsewhere. Most do not cause problems but some cause warts and cancers.
Warts are usually caused by strain 6 and 11. These strains are found in the gardisil vaccine we now give kids. Warts are a cosmetic problem only. They are not dangerous. We treat them with freezing, heat, lasers, and creams.
Cancers from HPV consist of cervical, penile, anal, and some throat cancers. Cervical cancer prevention is the entire reason women get Pap smears. Penile cancer is very rare in this country mostly due to circumcisions. Also men with access to health care come in pretty darn quick when something weird is on their penis. 
Anal cancer only occurs with receptive intercourse and mouth and throat cancers from performing oral sex. Those are also fairly rare. Strains 16,18, 31, and 33 cause most cancers while 16 and 18 are in the gardisil vaccine also.
Important to understand is that not everyone exposed to the virus gets a wart or precancerous penile or cervical change just like you don't catch every cold you are exposed to. Besides limiting exposure the best prevention is not smoking, drinking moderately, good nutrition and exercise, adequate sleep and good stress relief coping mechanisms.
If you have any other specific questions ask me.
Dr. PJ4
