Text figures

Text figures (also known as non-lining, lowercase, old style,[1] ranging, hanging, medieval, billing,[2] or antique[3] figures or numerals) are numerals designed with varying heights in a fashion that resembles a typical line of running text, hence the name. They are contrasted with lining figures (also called titling or modern figures), which are the same height as upper-case letters.[4][5] Georgia is an example of a popular typeface that employs text figures by default.

Hoefler Text, a typeface designed in 1991, uses text figures.
The ascending six and descending nines are minted on this 1996 U.S. penny.