ICO is a format (full name - Icon File) of bitmap images and refers to system files. Developed by Microsoft and designed to store icons in its operating system. ICO files, as a rule, store icon images - modest in size, with a small resolution (from 16x16 to 64x64 pixels), with different color depths (from 16 colors). In the graphical interface of various operating systems, ICO format files are used to display files, programs and folders (primarily in Windows) or as an icon for a specific website.
WebP is an open-source format for image files, raster images. Created in 2010 by Google for web graphics in order to quickly upload images to web pages. This is the main advantage of WebP files. Compression of images in this format can go with or without loss, depending on what level of quality you want to achieve. Thus, lossless compression is 26% better than in PNG files. If quality loss is acceptable, then compression in WebP format is 25-34% better than in JPEG files. Full support for WebP is not yet available on Firefox, Internet Explorer, and Safari.