What is the letter a in caneiform writing?

There is no letter "a" in cuneiform writing. Cuneiform is a writing system that uses wedge-shaped marks to represent syllables, not individual letters.

To represent the sound "a", cuneiform uses a variety of signs depending on the context and the specific syllable. For example:

* A at the beginning of a word is often represented by the sign 𒀀 (a).

* A within a word can be represented by various signs, such as 𒀀 (a) or 𒊒 (an).

To learn more about cuneiform writing and its signs, you can consult resources like the Cuneiform Digital Library Initiative (CDLI) website or explore books and articles on ancient Mesopotamian languages.