What is a jpeg?

I get a lot of questions about the different file formats, so I figure I can go through them one at a time. I guess to start the discussion, we should really go from the basics. There are two types of art files, vector files and bitmap or raster files. Illustrator and Corel are the most popular vector art programs. Vector art is mathematical, it is geometric definitions of the designs, which allows those file to be infinitely scalable. Bitmap, or raster images are grids, and each square in the grid is defined by a color. You can easily turn any vector file into a raster file, but going back is a lot more difficult. That being said, no organization should be stuck with a jpg alone, but jpgs are great files. They can be used on the web, inserting into word files, or even into powerpoint documents. Now sometimes, you may try to insert a jpg into a word document, lets say, and you will only see a black box, or a box with a red "X". This normally means that the jpg is in the wrong color format, CMYK instead of RGB, but those are later posts. The jpegs are set restrict by the size of those blocks, known as dots per inch or DPI. The number of dots, or color blocks, per inch determine how crisp the image is. If there are only 72 dots per inch, as is the standard on the Internet, can not be used in professional printing, which has a standard of 300 dots per inch. What does that mean, please don't pull a logo off of a website and try to print it in a brochure.