Brazilian slums have long been left out of modern maps, but a combination of escalated violence and the attention that the World Cup brought to the area has brought that to light -- Google and Microsoft are now including the favelas in Rio de Janiero on maps.

Favelas are dense working-class neighborhoods which officials considered eyesores, the Wall Street Journal reported.

As a result, they refused to send in cartographers or provide official addresses. But frustrated residents began mapping the communities themselves in order to get the government's attention and push for more public services.

Google and Microsoft have begun mapping the favelas, using the contributions of community groups, to ensure that every twisting, narrow alleyways to every hole-in-the-wall laundromat is covered.

"The power of putting [favelas] on a map and giving them an online presence is really important to opening them up and getting them integrated into the city," says Esteban Walther, Google's director of marketing for Latin America.

The slums came into the spotlight before the World Cup took place because of increased violence, The Guardian reported in May.

Amnesty International revealed that 80 percent of Brazilians were afraid of being tortured by their own police force, higher than the international average of 44 percent based on 21 countries surveyed.

In 2008, when the residents called on the government to right violence caused by drug gangs, which resulted in the formation of the Pacifying Police Units (UPP), the Guardian reported.

Although the Brazilian media reports positively on the UPP, residents of Rocinha -- the largest favela -- say policemen in the unit are abusive and violent.

The efforts of Google and Microsoft are motivated by potential profits, as well as opening the favela up to the businesses of the outside world -- especially since the residents are engaged with technology such as cell phones.

"A lot of companies are doing this because they know that these are customers and they're no longer excluded from the economic system of Brazil," Ronaldo Lemos, the director of the Institute of Technology and Society in Rio de Janeiro, told the WSJ. "It's good business to map the favelas."

Microsoft intends to map 40 favelas by the end of the year, and move the program to other developing countries.

Google is targeting the three largest favelas, Rocinha, Caju and Vidigal, with the nonprofit AfroReggae.