For CSS, both px and pt are (supposed to be) physical sizes: 1 px = 0.75 pt
1 px = 1 pixel was the original intention but has not been true for a long time now.
The problem is that some people use HDPI screens without (adequate) display scaling - likely to recover screen space from existing bloated desings - and then base their own designs on that. So neither px nor pt end up referring to physical sizes in practice.
1 px = 1 pixel was the original intention but has not been true for a long time now.
The problem is that some people use HDPI screens without (adequate) display scaling - likely to recover screen space from existing bloated desings - and then base their own designs on that. So neither px nor pt end up referring to physical sizes in practice.