Like fingerprints and everything that makes us unique from one another as humans, belly buttons on every individual take different shapes and sizes.
Before I let you into the world of the types of belly buttons, you should first understand how belly buttons are formed.
Belly buttons, also known as navel, are the remnant of a baby's umbilical cord, which, before birth, connects a baby to its mother during pregnancy. Once the umbilical cord is cut, it is taken care of till the leftover umbilical cord (stump) dries up and falls off to reveal the baby's navel.
Now, let's look at the types of belly buttons that we have. While the most known belly buttons are the 'innie' and the 'outie', many other different belly button shapes exist. Below are common variations of the most popular belly buttons;
Protruding (outie): Protruding belly buttons are popularly called "outies." An estimated 10 per cent of the population has an outie belly button, with the remainder possessing an "innie,". An outie often occurs when the stump from the cut umbilical cord goes out instead of in.
Deep hollow (innie): This belly button typically appears if there's a shadow underneath the belly button's top fold. This belly button type resembles a slightly open mouth. Most people in this category may have a "funnel" belly button, which is common if they have excess abdominal fat.
Round: This belly button looks close to an outie belly button but isn't. A round belly button is concave-like or protrudes inward. It is also often called an oval belly button. Although it doesn't have any hooding or covering, instead, it appears symmetrically rounded.
Vertical (typically narrow): Some doctors call a vertical belly button a "split" belly button because it looks like the portion of the stomach makes a slight up-and-down split. This belly button has very little hooding over its top, making it look much like the small case of the letter "I" imprinted on the skin. This is considered the most common belly button type over the years.
Horizontal (typically narrow): This belly button is called the T-type belly button. It has most of the belly button fold going horizontally. A downturn at the top of the belly button may look like the line that crosses a "T." This button type differs from the deep hollow belly button because the top portion of the skin almost completely covers the innermost portion.
Light bulb: This belly button has very little hooding on the top with a slightly oval shape that narrows as it goes down, making it look very much like a light bulb. Some compare this belly button to a wine bottle or upside-down beer.