See the R page for more discussion about the derivation of miniscules, majuscules, and our alphabet.
Detail of a printer’s type case [Diagram by Rudolph Ruzicka for Printing Types — Their History, Forms and Use, by D. B. Updike]
tion. Capitals were put in the upper case because they were less frequently used, miniscules (what we know as lowercase today) were put down below, and closer to the typograher. The technical term for capitals or upper case letters are majuscules.