Recycling is nothing new: It's been around for about as long as humans have used tools. Industrialization and mass-production technology, however, have made it cheaper to make things -- and easier to throw them away. The 20th century invention of the modern landfill made excessive waste more respectable.
Recycling grew popular again with the environmental movement of the 1960s and '70s, and the now-ubiquitous recycling symbol -- reduce, reuse, recycle -- was born. Cities eventually began offering recycling pickups, and now many U.S. locales require it. Americans rank seventh among nations in recycling, according to National Geographic and GlobeScan's 2012 Greendex.
Pictured: Scrap metal is processed at Jewometaal Stainless Processing BV plant in Rotterdam. Recycling steel is profitable, and more steel is recycled each year in the U.S. than paper, plastic, aluminum and glass combined.
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