Summarize this article:

HPV can spread through any skin-to-skin contact involving the genitals. This can happen during vaginal sex, anal sex, hand-to-genital contact, genital-to-genital contact without penetration, and (rarely) oral sex. HPV can remain in your system for years without causing symptoms. This means you could still have HPV even if you have not recently had sex, or if you have only been having sex with one partner.  You cannot get HPV from shaking hands or from inanimate objects such as toilet seats (except possibly shared sex toys). The virus does not spread through the air.  Condoms do not protect you completely from HPV, but they may reduce the chance of transmission. Some strains of HPV can cause genital warts: lumps or growths in the genital or anal region. These are considered low risk strains, since they rarely lead to cancer. If you're not sure whether you have genital warts, compare your symptoms to the following:  The most common location for genital warts in men is under the foreskin of an uncircumcised penis, or on the shaft of a circumcised penis. Warts can also appear on the testicles, groin, thighs, or around the anus.  Less commonly, warts can appear inside the anus or urethra, causing bleeding or discomfort at the toilet. You do not need to have anal sex to get anal warts.  The warts can vary in number, shape (flat, raised, or cauliflower-like), color (skin-colored, red, pink, grey, or white), firmness; and symptoms (none, itchiness, or pain). HPV rarely causes cancer in men. Even though almost every sexually active person has been exposed to HPV, it only causes anal cancer in about 1,600 U.S. men a year. Anal cancer can begin without any obvious symptoms, or with one or more of the following:  Bleeding, pain, or itching of the anus. Unusual discharge from the anus. Swollen lymph nodes (lumps you can feel) in the anal or groin area. Unusual bowel movements or a change in the shape of your stools. About 700 U.S. men each year are diagnosed with HPV-caused penile cancer. Possible signs of early penile cancer include:  An area of penis skin becoming thicker or changing color, usually on the tip or foreskin (if uncircumcised) A lump or sore on the penis, usually not painful A reddish, velvety rash Small, crusty bumps Flat, bluish-brown growths Smelly discharge under the foreskin Swelling at the end of the penis HPV increases the risk of cancer in the throat or back of the mouth (cancer of the oropharynx), even if it's not the direct cause. Possible signs include:  A persistent sore throat or ear pain Difficulty swallowing, opening the mouth fully, or moving the tongue Unexplained weight loss Lump in the neck, mouth, or throat Hoarseness or voice changes that last more than two weeks Certain characteristics make an HPV infection more likely. Even if you are not showing symptoms, it's a good idea to educate yourself about possible medical checkups and treatments if you fall into any of these categories:  Men who have sex with men, especially those who receive anal sex Men with compromised immune systems, such as those with HIV/AIDS, a recent organ transplant, or immunosuppressant medication Men with many sexual partners (of any sex), especially if condoms are not used Heavy use of tobacco, alcohol, hot yerba mate, or betel increase your risk of some HPV-linked cancers (especially in the mouth and throat).  Uncircumcised men might be at higher risk, but the data is unclear.

Summary:
Understand how HPV is transmitted. Identify genital warts. Look for signs of anal cancer. Identify penile cancer. Watch for signs of throat and mouth cancer. Be aware of risk factors for HPV in men.