Six sigma can trace is success back to the time of the 17th century, when a man named Carl Frederick Gauss introduced the concept we know as the normal curve. Moving a little bit forward in time, six sigma can find its roots in the 1920s when math-tastic Walter Shewhart showed that in a line, three sigmas from the mean will become the point where a certain process will require some form of correction. After such a startling revelation in the realm of statistics, several types of standards for measurements soon followed among of which we might be familiar with, such as zero defects and cpk.
These came at a much later time, but the term six sigma will be credited to an engineer who works for Motorola and goes by the name of Bill Smith. As it turns out, the term six sigma is a trademark that is federally registered and owned by Motorola. Jumping to the decade of the eighties will bring about Motorola head honcho Bob Gavin as the sole revolutionizer of total quality management by deciding that the traditional levels of quality in order to measure defects in around a thousand opportunities is not enough to provide much granularity. Galvin decided that it was time for a new standard, one that could measure defects going as far up as a million opportunities per each one. Thankfully, Motorola engineers were able to develop this new standard and has thus created a methodology powerful enough to change the face of total quality standards in the realm of business.