During the terrorist attacks that killed 130 people in Paris, large numbers of residents and visitors to the city used social media to let loved ones and officials know they were hiding from the ISIS gunmen, injured, or safe and out of harm's way.
Facebook said last week that it would widen the deployment of the tool, which is based on a technology originally created in the wake of the Japan's 2011 tsunami and Fukushima nuclear plant disasters, in order to give people a way to notify loved ones and others of their whereabouts. Facebook previously deployed the tool during Typhoon Ruby in the Philippines, Tropical Cyclone Pam in the South Pacific, and earthquakes in Chile, Nepal and Afghanistan.
The American Red Cross and Google also have set up accountability systems through social media to effectively notify authorities that large numbers of people are out of harm's way. The Red Cross created the Safe and Well app following Hurricane Katrina, which devastated the Gulf Coast in 2005. The app allows people to search for missing or unaccounted for loved ones who have registered on the site in the aftermath of a disaster or mass casualties.