Biotechnology is the exploitation of living systems or molecules from them for commercial gain. Although the word 'biotechnology' is only a few decades old, humankind has been using biotechnology for millennia, for example in baking, brewing and sewage treatment. Modern biotechnologies rely on our increasing ability to manipulate organisms at the genetic level and include novel waste treatments and bioremediations, new pharmaceuticals, the exploitation of enzymes in 'green catalysis' and exciting new diagnostic techniques. In the 20th century our lives were transformed by information technology; the 21st century may see an equally great transformation, but this time led by biotechnology.