How It's Made simplify overdubbing in different languages. For example, the show currently avoids showing a narrator or onscreen host, does not often have employees of featured companies speak on camera, and keeps human interaction with the manufacturing process to a bare minimum. An off-screen narrator explains each process, often with humorous puns. Each half-hour show usually has three or four main segments, with each product getting a demonstration of approximately five minutes; exceptions are allowed in the allotted time for more complex products. Usually, every show has at least one product with a historic background note preceding it, showing how and where
Whiskers whiskers use a variety of techniques, including temporary deprivation either of the whisker sense or of other senses. Animals can be deprived of their whisker sense for a period of weeks by whisker trimming (they soon grow back), or for the duration of an experimental trial by restraining the whiskers with a flexible cover like a mask (the latter technique is used, in particular, in studies of marine mammals). Such experiments have shown that whiskers are required for, or contribute to: object localization, orienting of the snout, detection of movement, texture discrimination, shape discrimination, exploration, thigmotaxis, locomotion, maintenance of equilibrium,