Fakes and copies -- the words conjure up images of brand-name goods that aren't; trademarks purloined; forged money and passports; pirated CDs, software and videos . . . and even archaeological finds that weren't as historic as they were purported to be.
But look again. In the same society where such surrogates are frowned upon -- or even considered criminal -- there are many doubles that simply don't fit the negative stereotype.
More than that, fakes (things that pretend to be what they are not) and copies (reproductions of an "authentic" original) can be beneficial, educational or simply more accessible than the real thing. Whether it's patented drugs that put breakthrough treatments within the reach of developing countries, or an Impressionist print in a classroom that helps kids to appreciate art, many fakes and copies have a crucial role to play.