Basically, proto-Elamite signs can be divided into five groups according to their place and function in the sentence. Sentence is used here to denote each self-contained unit in a proto-Elamite text; the header, an entry, the subscript, or the total (see also Englund 2004, 105 figure 5.3a).
The five groups are:
Note that there exists some overlapping between the signs of groups 1, 2, and 3. The high number of singletons (non-repeated signs) in proto-Elamite is in good accordance with the characteristics of proto-writing as described by Damerow 1999. As was also shown for the so-called Indus Script the number of singletons will increase with each new text publication (Farmer, Sproat and Witzel 2004, 36). It remains to be studied whether the number of singletons in proto-Elamite decreased over time, and if proto-Elamite like proto-cuneiform, underwent some form of standardization during the late phase of its use (a reevaluation of the results reached in Dahl 2002 may be needed).