The Mozilla corporation is an open source group responsible for the Firefox browser and several other free and open source programs.
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GIMP stands for GNU Image Manipulation Program, and is a free software program for image authoring and composition, and photo retouching. The program has a scripting interface and can be expanded with plug-ins and extensions.
Conceptually, plug-ins are like Lego toys. They are software modules that add a specific feature or service to a larger system. A Lego wheel by itself isn’t that fun, but add that wheel to a Lego car, and you’re cooking with gas. Unfortunately, most plug-ins, whether for browsers or graphics programs, don’t provide as much functionality as a Lego wheel. For example, there are number of plug-ins for the Netscape Navigator browser that enable it to display different types of audio or video messages based on MIME types. However, if nobody develops those kinds of files, the plug-in is useless. There are some cool plug-ins for graphics programs, the best of which is Kai’s Power Tools. That adds a zillion effects that you can use on your images. By the way, in Photoshop you can activate plug-ins by holding down the command and shift keys when starting up the program.
Tables of data, that age-old way of comparing information by displaying items in columns and rows, weren’t possible in the earliest version of HTML. This is surprising since HTML was initially used by academics, and tables are their stock and trade. Eventually, however, tables came into existence and became officially supported with the release of HTML 3.2 in 1996. They have since evolved from their original purpose to become a convenient way to control the layout of text and images on a web page.