Declan Chidlow takes us on a really interesting tour of the often, under-reported world of print stylesheets, how to use them and also how to debug them.

Physical, absolute units

When we’re writing CSS, we tend to use relative, responsive units such as rem, em, etc, which scale based on user preferences and such.
Sometimes, I find myself forgetting that CSS even has units of standard, absolute measurements, but we have a lovely collection at our disposal. It is worth keeping in mind they aren’t always accurate on screen, but they usually are when physically printed.