Carbon foot print is hot terminology use now-a-days, its mean total amount of greenhouse gas produces by a person, company, event, product or organization. Carbon foot print can be measured by undertaking a GHG emissions assessment. Once the size of a carbon footprint is known, a strategy can be devised to reduce it, e.g. by technological developments, better process and product management.

Lower the Carbon footprint healthier would be environment resulted less harm to nature. Scholars suggest the most effective way to decrease a carbon footprint is to either decrease the amount of energy needed for production or to decrease the dependence on carbon emitting fuels. Everyone want clear environment. Yet the green movement gives premise that the resultant release of carbon dioxide to atmosphere in burning fuel in industries is not good because it is claimed to cause global warming.
 
Facebook has revealed the carbon footprint and energy use of its US data centers and has pledged to use 25 percent sustainable energy by 2015. Facebook currently gets 23 percent of its energy from clean and sustainable sources, 27 percent coal, 17 percent natural gas and 13 percent nuclear. Facebook has two US data centers, located in Oregon and North Carolina, as well as two co location facilities, one on the East coast and one on the West.

"We’re releasing this data because we believe in the power of openness, and because we hope that adding another data point to our collective understanding of our industry’s environmental impact will help us all keep improving," the company said in a statement.
 
The Face book company said that last year, its data centers and operations used 532 million kilowatt hours of energy, emitting 285,000 metric tons of carbon dioxide equivalent. In contrast to Google company which carbon footprint equaled nearly 1.5 million metric tons, more than five times Facebook's.
 
For a typical Facebook user, a year's worth of liking and posting consumes just 269 grams of carbon equivalent — "roughly the same carbon footprint as one medium latte," the company pointed out. "Or three large bananas. Or a couple of glasses of wine."

 “Unfortunately, the transparency Facebook exhibited today is still rare among companies who are racing to build our on line world.” said Gary Cook, a Greenpeace International analyst.
 
"Facebook looks forward to a day when our primary energy sources are renewable, and we are working with Greenpeace and others to help bring that day close," said Marcy Scott Lynn, one of Facebook's sustainability directors, when that deal was announced.

"As Facebook expands, we need more data centers to power our platform, more office facilities for our employees, and more energy for both," the company said.

However, Facebook’s siting policy prioritizing clean energy for new data centers will help it meet and eventually exceed its goal, and other companies who want a clean cloud should make a similar commitment.
 
The menace of the greenhouse effect is threatening to tear the earth apart as climate change has become the greatest challenge of our time. Climate change is a fundamental issue of social justice and peace in our world.  Climate change will devastate the poor most directly and will create conditions for new conflicts over land and water resources. Being carbon neutral means having a net zero carbon footprint, or achieving net zero carbon emissions by balancing a measured amount of carbon released with an equivalent amount offset, or buying enough carbon credits (tradable certificate or permit representing the right to emit 1 ton of CO2) to make up the difference.
 
The government needs to implement policies that ensure more sustainable and more efficient use of energy by all industries. It is also the government’s duty to tax high carbon emitters and  help support the use  of renewable energy given its low-carbon profile.