The history of written Sumerian can be divided into several periods:
• Archaic Sumerian – 31st–26th century BC
• Old or Classical Sumerian – 26th–23rd century BC

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The standard variety of Sumerian was Emegir (𒅴𒂠 eme-gir₁₅). A notable variety or sociolect was Emesal (𒅴𒊩eme-sal), possibly to be interpreted as "fine tongue" or "high-pitched voice" (Rubio 2007, p. 1369). Other terms for dialects or registers were eme-galam "high

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Sumerian is a language isolate. Ever since decipherment, it has been the subject of much effort to relate it to a wide variety of languages. Because it has a peculiar prestige as one of the

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Development
The Sumerian language is one of the earliest known written languages. The "proto-literate" period of Sumerian writing spans c. 3300 to 3000 BC.

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Assumed phonological or morphological forms will be between slashes //, with plain text used for the standard Assyriological transcription of Sumerian. Most of the following examples are unattested.
Phonemic inventory
Modern knowledge of

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Ever since its decipherment, research of Sumerian has been made difficult not only by the lack of any native speakers, but also by the relative sparseness

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The key to reading logosyllabic cuneiform came from the Behistun inscription, a trilingual cuneiform inscription written in Old Persian

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