A unicase or unicameral alphabet is a writing script that has no separate cases for its letters. Semitic abjads such as Hebrew and Arabic, Brahmic scripts such as Devanagari, Tamil and Thai, Chinese characters, Hangul and the Iberian and Georgian scripts are unicase writing systems, while scripts like Latin, Greek, Cyrillic and Armenian are bicameral, as they have two cases for each letter, e.g. B and b, Б and б, Β and β, or Բ and բ. Individual characters can also be called unicameral if they are used as letters with a generally bicameral alphabet but have only one form for both cases; for example, the ʻokina as used in Polynesian languages and the glottal stop as used in Nuu-chah-nulth are unicameral.
Most modern writing systems originated as unicase orthographies. The Latin script originally had only majuscule forms directly derived from the Greek alphabet, which were originally viable for being chiseled into stone. At the same time, everyday writing was carried out in a cursive variant of the block capitals, which during the Middle Ages evolved into new letterforms for use in running text that were more legible and faster to write with an ink pen, such as Carolingian minuscule. Originally, use of the two forms was mutually exclusive, but it became a common compromise to use both in tandem, which ultimately had additional benefits in areas such as legibility. The later minuscule became the "lowercase" forms, while the original majuscule became the "uppercase" forms.