This file format is used to transmit image data. It contains a set of images that can be linked to form an animation. It is used to store non-compressed bitmap images in 24-bit color created using MTV ray tracer.
ICO is a file of this format usually contains a small image icons of different resolutions (16x16, 32x32, 64x64 pixels) and various color depths (16 colors, 32, 64, 128, 256, 16-bit, and so on). Used to display files and folders in the graphical user interface (GUI) operating systems. This format can be opened with the help of the program ACDSee.