A Win32 critical section enters the kernel when blocked. (Edit: nevermind, you're not disputing this) A pthread mutex on Linux won't enter the kernel when unco

A Win32 critical section enters the kernel when blocked. (Edit: nevermind, you're not disputing this) A pthread mutex on Linux won't enter the kernel when uncontended (thanks to futex -- this wasn't true ~20 years ago). I would say the terms are pretty synonymous, and implementation choices differ; sometimes implementation choices are implied by the name but I don't think everybody agrees on how those choices map to names.