There's a few factors that are considered responsible for development of skin tags.
Skin tags mostly develop in areas where your skin has folds and it rubs against itself such as:
In some cases skin tags may fall off on their own. But most people consider getting them removed because either they're in the way or they look unpleasant to them. If skin tags don't bother you, just embrace them. If you do decide to get rid of them, you have plenty of options.
Dermatologists remove skin tags using either a scalpel to cut them off, liquid nitrogen to freeze them, or heat to burn them off. Each of these methods are considered safe and effective. Sure there may be some scarring or redness after the removal, but it is very common and usually goes away with time.
You may also use professional devices such as Aven Buzz Skin Tag Remover Pen to remove skin tags by heating them. This process is known as cauterization where the heat is passed on to the skin tag using a probe. Once the skin tag is burned off, it just falls off.