Brackets, parentheses, this forum and my screen

Here I often see references to a "bracketed phrase" appear in parentheses on my screen. Is that my font settings or your software or do many people use the terms brackets and parentheses differently?

Perhaps a test is indicated: brackets [], parentheses ().

A parenthetical element in a sentence is enclosed by parentheses. They may be commas, dashes or some variety of bracket. In mathematics, square brackets have been named parentheses to distinguish them from curved brackets.