This document describes PNG (Portable Network Graphics), an extensible file format for the lossless, portable,
well-compressed storage of static and animated raster images. PNG provides a patent-free replacement for GIF and can also
replace many common uses of TIFF. Indexed-color, greyscale, and truecolor images are supported, plus an optional alpha
channel. Sample depths range from 1 to 16 bits.
They are using them, however. They’re visiting websites with them, using apps with them, and so forth.
OK, and the kernel is written in C and assembly. Should they know both of those as well?
No, but it should still work. Getting rid of alpha channels would break all of that.