ONLINE GLOSSARY

0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Click on a letter to browse through the Glossary terms.
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• Radian. Special unit of measurement for calculating values related to angles, circles and arc lengths. Also used in trigonometry. Technically speaking, the radian is a "dimensionless unit" which may be confusing. Many common mathematical formulas require values to be input in radians or produce results measured in radians. In this event, it is necessary to convert radians to degrees and vice versa. A straightforward formula can be used to accomplish this and many scientific calculators have a built-in function for converting between the two forms of angle measurement.
  
  
• Radius. The distance from the exact center of a circle to the outside edge or circumference. This distance is exactly one half the diameter of the circle.
  
  
• Regular Helix. See Helix.
  
  
• Regular Polyhedron. One of five special types of polyhedrons (or "polyhedra") where the same number of sides or "facets" always come together at each point or vertex. See Platonic Solids.
  
  
• Regular Pyramid. A "right" (i.e. upright, not oblique) pyramid with a base in the shape of a regular multigon. (A regular multigon is a two-dimensional shape with three or more sides that are all identical in length.)
  
  
• Removed View. A view created to illustrate an object, detail or feature positioned in such a location that it cannot be clearly seen in any normal view.
  
  
• Resolve. To uncover, deduce, reconstruct or calculate based on available information, i.e. to "fill in the blank" using existing information as a guide. If the blueprinting process is imagined as being similar to solving a picture puzzle where some pieces are missing, existing information could be used to reconstruct or resolve the puzzle to find the missing pieces.
  
  
• Revolution. The process of revolving an object or feature about an appropriate centerline until it is parallel with a normal view. The goal of revolution is to find a view of the part where it appears true length or true size and can therefore be measured. This technique is a practical alternative to the process of creating an auxiliary view. See also Conventional Revolution.
  
  
• Revolved. Rotated about an appropriate centerline using the process of revolution. A "revolved view " is a true size representation created by revolving an object or feature until it is parallel with a normal view. This is often a quick and easy alternative to the process of creating an auxiliary view.
  
  
• Revolving. The process of rotating an object or feature about an appropriate centerline. See Revolution and also Revolved.
  
  
• RGB. An acronym that means "Red, Green, and Blue." RGB represents what is known as a "color space" and is the method both televisions and computers use to display images on screen. In contrast, CMYK is the format used by printing presses and color printers to create color images using four different colors of ink. Digital image files that will only be viewed on screen or sent to others via e-mail should be scanned and saved in RGB format. (On the other hand, images that are to be printed on any sort of printer should be scanned and saved in CMYK format.) RGB images contain slightly less information and therefore takes up less computer memory than images saved in CMYK format. See also Bitmap Image, Grayscale, Monochrome.
  
  
• Right Cone. An "upright" (i.e. not oblique) cone that does not "lean" to one side. If a line is drawn between the exact center of the circular base and the tip of a right cone, it will be normal (i.e. perpendicular) to the plane containing the base of the cone.
  
  
• Right Cylinder. An "upright" (i.e. not oblique) cylinder that does not "lean" to one side. Both the base and the top of a right cylinder are parallel. In addition, a line drawn between the exact center of the circular base and the exact center of the circular top is normal to both surfaces.
  
  
• Right Prism. An "upright" (i.e. not oblique) prism that does not "lean" to one side. Both the base and the top of a right prism are parallel. In addition, a line drawn between the exact center of the base and the exact center of the top is normal to both surfaces.

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0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Click on a letter to browse through the Glossary terms.
To download a printable version of the entire Glossary, click here.

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