"I have a duty to act on cyber bullying"

The Duke of Cambridge has made a speech today at a big conference called the Children's Global Media Summit.

At the conference in Manchester, he spoke of his 'worry' at how technology can affect children and identified online bullying as a big problem.

Together with social media companies, charities, parents and young people, he talked of his plans to make changes and his aim to encourage children to be "smarter, stronger and kinder".

He also announced the new BBC website called 'Own It' which is for young people aged 9 to 12 years old. It offers them advice on how to handle bullying online.

The organisation aims to make children "smarter, stronger and kinder".