The first known writing?

The Tărtăria tablets are three tablets, discovered in Tărtăria, Alba County, Romania. They bear incised symbols that have been the subject of considerable controversy among archaeologists, some of whom claim that the symbols represent the earliest known form of writing in the world.

The tablets were found in 1961 at about 30 kilometres from the well-known site of Alba Iulia. Nicolae Vlassa, an archaeologist at the Cluj Museum, unearthed three inscribed but unbaked clay tablets, together with 26 clay and stone figurines and a shell bracelet, accompanied by the burnt, broken and disarticulated bones of an adult male. Two of the tablets are rectangular and the third is round. They are all small, the round one being only 6 cm across, and two – the round one and one of the rectangular ones – have holes drilled through them.
All three have symbols inscribed only on one face. Similar motifs have been found on pots excavated at Vinča in Serbia and a number of other locations in the southern Balkans. The unpierced rectangular tablet depicts a horned animal, another figure and a branch or tree. The others have a variety of mainly abstract symbols. The purpose of the burial is unclear, but it has been suggested that the body was that of a shaman or spirit-medium.

The tablets are generally believed to have belonged to the Vinča culture, which at the time was believed by Serbian and Romanian archaeologists to have originated around 2700 BC. Vlassa interpreted the Tărtăria tablets as a hunting scene and the other two with signs as a kind of primitive writing similar to the early pictograms of the Sumerians. The discovery caused great interest in the archeological world as it predated the first Minoan writing, the oldest known writing in Europe.
However, subsequent radiocarbon dating on the Tărtăria finds pushed the date of the tablets (and therefore of the whole Vinča culture) much further back, to as long ago as 5500 BC, the time of the early Eridu phase of the Sumerian civilization in Mesopotamia (although this is disputed in the light of apparently contradictory stratigraphic evidence).

If the symbols are indeed a form of writing, then writing in the Danubian culture would far predate the earliest Sumerian cuneiform script or Egyptian hieroglyphs. They would thus be the world's earliest known form of writing. This claim remains controversial.

The meaning (if any) of the symbols is unknown, and their nature has been the subject of much debate. Scholars who conclude that the inscribed symbols are writing base their assessment on a few conclusions, which are not universally endorsed. First, the existence of similar signs on other artifacts of the Danube civilization suggest that there was an inventory of standard shapes of which scribes made use. Second, the symbols make a high degree of standardization and a rectilinear shape comparable to archaic writing systems manifest. Third, that the information communicated by each character was a specific one with an unequivocal meaning. Finally, that the inscriptions are sequenced in rows, whether horizontal, vertical or circular. If they do comprise a script, it is not known what kind of writing system they represent. Some archaeologists who support the idea that they do represent writing, notably Marija Gimbutas, have proposed that they are fragments of a system dubbed the Old European Script.