Subtitle: Finding a new bump or growth on your skin can be startling. The good news? The vast majority of warts are completely harmless.

Let me tell you about the first time I found a wart.

I was a teenager, and a small, rough bump had appeared on my thumb. I had no idea what it was. I picked at it (bad idea), tried to cut it off (worse idea), and spent days worrying that it might be something serious.

It was just a wart. A common, harmless, annoying little thing that eventually went away on its own.

But I didn't know that at the time. I didn't know what warts were, why they appeared, or how to treat them. I just knew I wanted it gone.

Now, after years of research and personal experience, I know that warts are common, manageable, and—most importantly—not something to panic about.

Here's everything you need to know about the 6 types of warts, how to treat them at home, and when to call the doctor.

🔬 The Science: What Exactly Is a Wart?

Before we look at the types, it helps to know what causes them.

Warts are not a sign of aging, and they aren't caused by touching frogs! They are caused by the Human Papillomavirus (HPV) . There are over 100 different strains of HPV, and different strains cause different types of warts.

When this virus enters the top layer of your skin (usually through a tiny scratch or cut), it causes the skin cells to multiply rapidly. This overproduction of keratin (the hard protein that makes up your skin, hair, and nails) creates the rough, hard bump we call a wart.

Because they are viral, they can be contagious, which is why you should never pick at them! They can spread to other parts of your body or to other people.