1. Pictographic Stage (3200-3000 BCE): This earliest stage consisted of simple, pictorial symbols that directly represented objects or ideas. Think of them as a simplified form of hieroglyphics. These symbols were carved onto clay tablets using a stylus.
2. Ideographic Stage (3000-2700 BCE): During this stage, the symbols began to represent not only objects but also abstract concepts and ideas. They were also starting to be used in a more systematic way, with certain symbols representing specific sounds. The number of signs increased as they started to represent both concrete and abstract concepts.
3. Syllabic Stage (2700 BCE onwards): This stage is the most advanced and developed, and the one we associate with cuneiform writing. The symbols shifted from representing whole words or concepts to representing syllables. This allowed for a much wider range of sounds and words to be written. The system became fully phonetic, enabling the writing of any word in the language. The cuneiform writing was adapted for various languages, including Sumerian, Akkadian, Elamite, and Hittite.
It's important to note that these stages aren't strict cut-offs but rather gradual transitions. The development of cuneiform was a continuous process that spanned centuries and saw various innovations and adaptations.