It’s been around for ages, well since ancient times, with both the Aztec and Maya people carrying out tongue piercing during religious ceremonies.
The most popular tongue piercing is a single piercing though the middle of the tongue. Alternatively two horizontal piercings on either side of the tongue is known as a venom bite.
The same piercings in a vertical manner are sometimes referred to as an angel bite (although this term is more commonly used for a double madonna lip piercing).
The swelling can last up to 4 weeks but will subside, at which point your piercer will replace your barbell with a shorter length. Of course, if you are at all worried about your new piercing you should contact your piercer as soon as you can.
You can also have your tongue frenulum pierced; this is the bit under your tongue that anchors it to the floor of your mouth.