ART file format
ART files are most commonly associated with America Online (AOL). An image file format was initially developed by the Johnson-Grace company, which was later acquired by AOL; ART format is the proprietary format used exclusively for all bitmap images available on the AOL franchise of services. Therefore, it is not surprising that viewing many images and graphics editing programs do not support the ART file format. To view, modify, or save ART files, open the source code files with an AOL client software, and 'Save As' more common and compatible file formats.
ART files comprise a single, highly compressed image. AOL developed the image format to speed up the average download time of images and web pages containing ART images. During file size reduction, the image quality may be significantly reduced. However, the format can be used with special software that can analyze the image file and subsequently determine the best compression technique that will ensure the retention of image quality. For image quality, the ART image file is quite similar to its JPEG equivalent.