Its good information to know… no harm in asking!
Most commonly used would be hex codes. The only time I ever use a colour name is when Im planning out my layout and not ready to muck with the actual colour scheme yet. Thats likely just a personal preference thing, but I rarely ever use red, blue, green, etc… I want a very specific hue of my chosen colour, so hex codes it is.
I have used RGB but trying to remember why off the top of my head and can’t…its happened and when I do theres a particular reason for it, but if I can Ill use hex.