Commonwealth Scientific and Industrial Research Organisation (CSIRO) researchers have come up with a new online tool 'We Feel' that can analyse around 27 million tweets per day and then relate them to different emotions, including love, joy, anger, surprise, sadness and fear.
The CSIRO has take up this project for mental health organisation Black Dog Institute.
The Institute is trying to understand how social media can help in reading the poor mental health of the people and it changes with time and place.
Helen Christensen, executive director of the Black Dog Institute, said the organisation can make a difference to the mental health of a nation by understanding the way its people use social media.
It was found that joy was the biggest emotion experienced by around 320 million Twitter users across the globe from April 29 to May 5 this year. Other feelings were sadness, anger and fear.
The software also found that women are less sad during the middle of the day but as weekend approaches, their sadness increases. But it is just the reverse for men. Christensen said this is "hardly surprising".
The tool to collect and process the tweets, which was developed by Amazon Web Services, found that people living in North America are the saddest and angriest of all nations and Australians are the most joyful but fearful.