What is an internet challenge?

Adolescents who challenge each other and do crazy things is of all times. Nowadays you can find a new challenge on the internet almost every day. There are many types of challenges and luckily most are funny and innocent. The challenges are filmed by teenagers and then shared via internet and social media. As a result, the spread is extremely fast.
But unfortunately there are also life-threatening challenges (link to Challenges sub-page). The videos mainly show the nice side but not what can go wrong. Often these challenges are popular for a short time, but there are challenges such as the choking game that have been around for a long time and can even become addictive.