The internet was once considered a great equaliser, a platform that could bring strangers together, even across racial boundaries. But internet users of the same race have recently begun clustering on certain social media websites.

Micro-blogging website Twitter has seen an upsurge in traffic from Hispanic and African-American audiences. These groups now claim about 30% of the site's user base, according to third-party statistics website Quantcast.com.

Read the whole story at BBC.co.uk