Windows Bitmap (BMP) or device-independent bitmap (DIB) is a format for raster images that was developed for the operating systems Microsoft Windows and OS/2. This format stores images of differing depths of color but does not support shades of gray. (The shades are simulated as colors.) Metadata is not supported. Even though bitmaps are not generally compressed, simple compression (RL compression) is possible. For this reason, BMP files are typically larger in file size than other formats such as PNG.