Based on a study of 173 million tweets, terrorism and racism have emerged as the top two global issues discussed on Twitter.
Terrorism was found to be the most discussed issue from the UN list of issues with 31 million tweets per year, the Telegraph reported on Friday.
The study conducted by SOAS University of London used the list of most pressing world issues for the study.
It was followed by racism with 28 million tweets, while climate change and human rights were listed on the third and fourth spots.
Overall, 60 per cent of the total analysed tweets focused on racism and terrorism on the social networking site.
"We found in the course of our research that 88 per cent of the tweets have negative connotations, which means that the subject is perceived by the individual as a problem that needs to be addressed or that cannot be resolved," the report quoted Richard Hammond, a data researcher on the project, as saying.
The study also noted that 88 per cent of the 173 million analysed tweets were negative in nature.