As the torrential rains in Chennai continued for the fourth straight day, with power and telephone lines down in many areas owing to flooding, Facebook's Safety Check feature would allow people to mark themselves as 'safe' from the floods. The feature, which debuted in October 2014, allows Facebook to ask users whether they're safe if located near a natural disaster.

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Fund raising campaigns are also afoot on social networking websites. "Help us get food and other essentials to those stranded in Chennai due to floods," reads a link shared by a Facebook user, Satish Sabapathi.

In an effort to provide all critical information related to floods in the city at one place, Google has created the Crisis Response tool - 'South India Flooding' - which enables users access to  emergency helpline numbers, crowdsourced list of places and people offering shelter, map of crowdsourced flooded streets and other such important information. It also offers important tweets, updated news and videos on Chennai floods.

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