Did the Balkan-Danube script possess a merely visual value or did it also have a phonetic one? Did it therefore express the sounds of an oral language in graphic signs? Today the script continues to maintain its secrets and it is still arguable whether it was made up of pictographic signs (representing objects or concepts by means of schematic, but quite realistic, drawings) and ideograms, or whether it associated written signs to a phonetic structure (in words or syllables). We do not even know what kind of language these populations actually spoke.

The proto-European script is probably logico-phonetic; it embodies both ideograms and signs corresponding to the spoken language. In particular, the ideographic symbols seem to indicate entire words and are prevalent both in number and role.

The phonetic component just performed an additional function, indicated by the small graphic markers (strokes, dots and arches) varying the root-signs. These markers could have been used to single out either syllabic segments (as in Egyptian hieroglyphs) or whole syllables (as in Akkadian cuneiform writing).

Summing up, the additional small graphic markers are used, when writing a text, to point out the different grammatical aspects or the implications of a basic concept expressed by an elementary sign, or else to indicate the phonetic element (probably a syllabic one) in a language unknown to us. (Merlini 2002a)
The logical-syllabic systems were more usual in archaic times. The proto-European one recalls the structure of the first Sumerian pictographic system, where there are only occasional phonetic (syllabic) values which were to become dominant in the later Akkadian cuneiform writing (Haarmann, 1997).