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As a computer science term, data binding is the substitution of a real value in a program after it has been compiled.
For example, during compilation a compiler can assign symbolic addresses to certain variables or instructions. When the program is bound, or linked, the binder replaces the symbolic addresses with real machine addresses. The moment at which binding occurs is called “bind time” or “link time.” In dHTML, data binding allows the client to look into a database and retrieve the content. This data can be automatically displayed in your table using the HTML data binding extensions, or you can manipulate the data with a script.
Producing images for the web invariably means minimizing the number of colors (and therefore the file size), and the index color system is another step in this squishing process. With a 216-color palette loaded, Photoshop will map an image to those colors when you move it into index color mode. While this helps the compression and allows you to choose bit depth, it also makes the colors dither, or shift numerically, to the palette. One way to compensate for dithering in the index mode is to use a histogram, which is basically a bar graph of each color’s frequency in the image. In most image-processing programs, you can manipulate the histogram and determine how much weight to give certain colors in the resulting palette.
Many image-processing programs, like Adobe Photoshop, allow you to build images in layers. These layers are created one at a time and placed on top of each other to assemble the whole image. While the file is a pile of little layered images, you can manipulate each layer individually and look at how each change will alter the completed picture.
Think of the food court at the mall. Most of the time, mallsters will go there looking for food in general, then decide what to eat after they’ve checked out the selection. The eaters benefit because they don’t have to wander all over the mall looking for lunch, and the feeders benefit from the added exposure. A referral network works in the same way. The web is perfect for this kind of marketing, since sites with similar audiences can be grouped just by linking them together. Amazon.com has an incredibly successful network of thousands of mini-bookstores. The small bookstores get more customers, and Amazon gets money for the books they sell to the little guys – a perfect symbiotic relationship.