Glossary of Design Terms
The imaginary line, defined by the flat base of a lower case letter such as “x”, upon which the bases of all upper and lower case letters apparently rest. The curved part of characters such as “o”, “c” and “a” actually fall below the baseline but appear, optically, to sit on it.
The fastening together of printed sheets into books, booklets, magazines etc. Common methods of binding include perfect-binding (glue binding), pad-binding, spiral coil binding, hardback binding, saddle-stitching and ring-binding. Binding also refers to the casing cover and spine of a hardback book as in “an old book with elaborate binding.”
Specifies how much color information is available for each pixel in an image. The more bits of information per pixel, the more available colors and more accurate color representation. For example, an image with a bit depth of 1 has pixels with two possible values: black and white. An image with a bit depth of 8 has 256, possible values. RGB images are made of three color channels. An 8-bit per pixel RGB image has 256 possible values for each channel which means it has over 16 million possible color values (256 x 256 x 256). RGB images with 8-bits per channel (bpc) are sometimes called 24-bit images (8 bits x 3 channels = 24 bits of data for each pixel). In addition to 8-bpc images, Photoshop can also work with images that contain 16-bpc or 32-bpc.
Also called raster images. These use a rectangular grid of picture elements (pixels) to represent images. Each pixel is assigned a specific location and color value. When working with bitmap images, you edit pixels rather than objects or shapes. Bitmap images are the most common electronic medium for continuous-tone images, such as photographs or digital paintings, because they can more efficiently represent subtle gradations of shades and color. Bitmap images are resolution-dependent—that is, they contain a fixed number of pixels. As a result, they can lose detail and appear jagged if they are scaled to high magnifications on-screen or if they are printed at a lower resolution than they were created for.
This is the art that extends past the crop marks, allowing for slight variations in trimming without these becoming obvious. The standard amount of bleed is 0.125″ although the printer may ask for more than this.
Also called body type or text face. The font used in setting the running text on a page in a book, website, magazine, catalog, brochure or other publication. A good body font should be easy to read, legible and provide differentiation between characters. Serif typefaces are typically chosen for large bodies of text.
A grade of writing and printing paper with a surface treated to take pen and ink well and have good erasure qualities. Cheaper grades of bond paper are made from all wood fiber; the better grades are made from rag fiber (cotton or linen fiber). Used where strength, durability and permanence are required.
A category or group of printing papers that have certain physical characteristics in common which make them suitable for the graphic arts. Used for books, magazines, brochures, fliers and most other reading material, with the exception of newspapers and pulp novels (mass market paperbacks).
Bits Per Channel. In Photoshop and other image editing programs, a file or image is dividied into channels based on the color space being used (i.e., a grayscale image uses one channel, an RGB image uses three channels and a CMYK image uses 4 channels). Thus in defining the bit depth of the image, one is actually defining the bit depth per channel. An RGB image, for example, actually has a bit depth of 24 as each of the three channels has 8 bits. When an image is referred to as “8-bit” or “16-bit” it is actually the “bits per channel” and not the overall bit depth.
1. Also called lightness/darkness or luminance. This refers to the perception of a color as to its proximity to black or white. Burgundy, Red and Pink have the same hue and saturation, but differ in Brightness (although, in some schools of thought white and black are “neutral”—being values of gray—and thus these three colors would vary in saturation as well as brightness). 2. In printing, the brightness of a sheet of paper measures the percentage of blue light it reflects. The brightness of a piece of paper is typically expressed on a scale of 1 to 100 with 100 being the brightest. Most papers reflect 60-90% of light. The brightness of a paper affects readability, the perception of ink color and the contrast between light and dark colors. “Bright white” refers to papers that are in the high brightness range (85% to 95%) and are visually “bluer” than regular white papers, which may have a yellow cast. The current trend in paper making is to make them as bright as possible.a