## Fine tailoring

Made to measure typically refers to clothing that is sewn from a standard-sized base pattern. A tailored suit is a common example of a made-to-measure garment. The fit of a made-to-measure garment is expected to be superior to that of a ready-to-wear garment, because ready-to-wear garments are constructed to fit the manufacturer's definition of an average customer, while made-to-measure garments are constructed to fit each customer individually.

## Differential calculus

In mathematical jargon, the derivative is a linear operator which inputs a function and outputs a second function. This is more abstract than many of the processes studied in elementary algebra, where functions usually input a number and output another number. For example, if the doubling function is given the input three, then it outputs six, and if the squaring function is given the input three, then it outputs nine.

## Good vibrations

Modern surfboards are made of *polyurethane* or *polystyrene* foam covered with layers of fiberglass, cloth and polyester or epoxy resin. The result is a light and strong surfboard that is buoyant and maneuverable. Recent developments in surfboard technology have included the use of carbon fiber. Each year, approximately 400,000 surfboards are manufactured.