There's little doubt that the 20th century was full of technological breakthroughs and scientific discoveries that changed history.
But the 21st century could go one step further, and investors need to be ready to see the opportunities in technologies that create a new market or disrupt an existing one.
In the last decade, we've seen iTunes turn the music industry on its head. The emergence of smartphones such as the BlackBerry and the iPhone, along with the social media revolution, has transformed the way we communicate.
What will be next? Research analysts at Citigroup have been investigating the innovations that could challenge the status quo.