Glossary B

B2B (B2C-e-marketplaces)	(n) Business communities are beginning to form e-marketplaces, enabling them to automate and leverage transactions with one another as a community. By bringing together large numbers of buyers and sellers, e-marketplaces give sellers access to new customers, expand the choices available to buyers and reduce transaction costs.
backface culling	(n) In rendering, a preprocessing step that removes all faces of the model that will be completely hidden from view.
bar graph	(n) A graph (usually 2-D) in which one dimension represents the independent variable and the other represents the dependent variable. The magnitude of the dependent variable is represented by a line or area of uniform width (a bar).
base feature	(n) The first feature created when defining a solid model. The base feature creates the initial geometry of the model from which additional geometry can be added or subtracted.
basic dimension	(n) A tolerancing measure used to describe the theoretically exact size of a feature.
basic size	(n) A tolerancing measure used to describe the theoretical size used as a starting point for the application of tolerances.
bearing	(n) A mechanical device designed to transfer radial or axial loads from a shaft while minimizing energy loss due to friction from the rotating shaft. Bearings are usually divided into two general categories: plain and rolling contact.
Bezier curve	(n) A special case of the B-spline curve. Unlike a standard B-spline curve, the Bezier does not provide for local control, meaning that changing one control point affects the entire curve.
BI (business intelligence)	(n) Consolidates and analyzes raw business data and turns it into conclusive actionable information. Enables companies to tap into disparate sources of customer, operational, and market data and then use this information to gain a competitive edge. It provides accompanies with the intelligence needed to spot trends, enhance relationships, reduce financial risk, and create new sales opportunities.
bicubic surface patch	(n) A 3-D freeform surface bounded by a set of curves described by third degree (cubic) functions. The bounding curves, often B-spline or Bezier curves, and their associated control points are used to manipulate the shape of the surface.
bill of materials	(n) A listing of parts or materials used in an assembled object. The listing is usually included as part of the working drawing of the full assembly.
binary tree	(n) A hierarchical, logical structure used to organize related elements. Each node on the tree is linked to exactly two leaves on the next level down. Binary trees are used to describe the relationship of geometric elements in a CSG solid modeler.
bird’s eye view	(n) In a perspective pictorial, a viewpoint looking down from above the object. From this viewpoint, the ground line is below the horizon line of the object.
blind hole	(n) A hole that does not go completely through the material. Blind holes can be created by any cutting device (such as a twist drill bit) that is capable of plunging into the material.
block diagram	(n) A relatively simple diagram that quickly identifies the relationships between systems, groups, people, or other physical or abstract entities. (See also flow diagrams.)
boldface	(adj.) A style of text in which the lines that make up the letters are thicker than normal. This technique is used to make words or letters stand out visually from the rest of the text.
bolt	(n) A mechanical fastening device with a head on one end of an externally threaded shaft. A nut is placed on the threaded shaft and rotated to clamp the material between the head and nut.
bonding	(v) A process in which a material (usually, a hardening liquid) is added to an assembly to hold parts together. Bonding is a permanent fastening method, using processes such as welding, soldering, brazing, and gluing.
Boolean operations	(v) Local operations used to define the relationship between two geometric objects. Boolean operations between new and existing geometry are used extensively to modify solid models in 3-D modeling software.
bottom view	(n) A principal view of an object, created by rotating the object 90 degrees about the horizontal axis below the front view. This view is not typically included in a standard multiview drawing.
boundary representation (B-rep)	(n) A popular method of representing solid models. This database structure describes the geometric and topological elements of the surface of the model. Unlike wireframe modeling, a B-rep explicitly defines the surface of the model. Unlike CSG modeling, a B-rep does not explicitly define the interior volume of the object.
bounding box	(n) An imaginary box representing the maximum dimensions of the object being drawn. Sketches of objects often begin with this box, and it is used to define the boundaries and guide the placement of individual features.
brainstorming	(v) A process used to identify as many solutions to a design problem as possible by freely suggesting ideas without criticism or discussion of feasibility. A brainstorming session will normally have a moderator and a recorder.
break lines	(n) Freehand lines used to show where an object is broken to reveal interior features of a part. Such lines can also be used to show where a portion of a line or object has been left out for clarity or because of space limitations.
broken-out section	(n) A section view used to reveal interior features of a part by breaking away a portion of the object. A broken-out section is often used instead of a half or full section view when the feature of interest is not symmetrical with the overall object. The result is a more efficient drawing. Unlike most other section views, a cutting plane line is not defined in an adjacent view.
B-spline curve	(n) A parametrically defined freeform curve that approximates a curve to a set of control points and provides for local control. Multiple 2-D curves are often combined to create 3-D surface patches.
bump mapping	(n) A rendering technique used to add surface detail to a model. Bump mapping perturbs the normals used in shading the surface polygons in such a way as to give the impression of a regularly undulating surface (i.e., texture). A golf ball could be represented as a shaded sphere, with the dimples created through bump mapping.