(CNN) – A world-first ban on major social media platforms for children under the age of 16 goes into effect in Australia on Wednesday. And regulators, parents and teenagers around the globe are watching closely to see how it plays out.

The law comes after years of concerns that social media platforms can cause addiction, body image issues, depression and other mental health issues for teens, as well as potentially exposing them to bullying or sexual exploitation.

Two Australian teens have already sued to block the law, claiming it violates their rights to political expression. And other critics have raised free speech and privacy concerns. (Read More)