JPG (also known as JPEG) is a common format of a file applied to digital photography and still images. JPG abbreviation stands for Joint Photographic Experts Group. That’s the committee that invented the given file type. The file extensions of JPG elements are .jpg and .jpeg. In fact, both of these are called JPEG images. This is the most widely used format of images produced by digital cameras. JPG images are also widely used on web resources of different types. JPG images are easy to handle by beginners and pros alike. One does not need to have any special skills to change the file size or apply quick modifications.
JPG images are known to have “lossy” compression, meaning that the file quality is lost as a file decreases. In web design, whenever a webmaster works with a page containing JPG images, the following algorithm is applied: the more a file is compressed, the faster a web page loads. As a result, this provides for a better UX on a web page. With every next compression boost, get ready to lose on the image quality.
Simply put, compressed images may result in the web audience noticing jagged pixels rather than smooth gradations between colors on the pages of a website.
JPG is great for photos. It supports RGB, Grayscale, and CMYK. It can reveal an unlimited number of colors in a 16-bit data format. Unlike other file formats (e.g. GIF), JPG can handle color gradation smoothly.
In addition to being used for photography, JPG file format is a great fit for still images, i.e. files with complex shades.
It’s better not to use JPG files for icons and buttons. JPG is better not to be used for drawings containing sharp lines. These can be displayed with visible artifacts, which affect the general visual appeal. For such purposes, PNG files can be a better alternative. These features lossless graphics format, so you may feel certain that no image data will be discarded.
One more peculiar feature of JPG files is that they do not support transparency. If you need to add a transparent background to a file, PNG format will be the best choice.
Whenever you create a JPG images from any different file format, make sure that you save the original file in the native format and create its JPG copy as well. This pro tip should be considered due to the lossy compression type of JPG files. As soon as a file data is discarded, you will hardly ever be able to recover it again.
Related terms: font, baseline, DPI.
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