letter case

In orthography and typography, letter case (or just case) is the distinction between majuscule (capital or upper-case) and minuscule (lower-case) letters. The term originated with the shallow drawers called type cases still used to hold the movable type for letterpress printing.Most Occidental languages (certainly those based on the Latin, Cyrillic, Greek and Armenian alphabets) use multiple letter cases in their written form as an aid to clarity. In addition, some computer programming languages use letter case to distinguish between special words, while others ignore case altogether.
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Noun
1. case for carrying letters
(hypernym) case