Writing itself is the first layer of written-text analysis in this notes context. We deliberately step around the physical act of speaking itself, phonetics and phonology, to start instead with how language is fixed on a page. It is a history of choosing a unit of representation. A pictogram depicts a thing in simplified form. An ideogram stands for an idea that cannot be pictured directly, such as heat or a legal paragraph. A logogram stands for a word, a morpheme, or a syllable.
Alphabet scripts go further. They represent the smallest contrastive unit, which can change an utterance’s meaning. Thus, looking at scripts means asking which linguistic level a system chooses to write down. Egyptian hieroglyphs mix phonograms for consonants, ideograms for concepts, and determinatives that reduce ambiguity, and the Chinese script, now mostly logographic, encodes words and morphemes rather than sounds. The Greek alphabet, derived from the Phoenician consonant script, added vowels and thereby moved the granularity down to the individual sound.
This history also corrects a tempting myth. Writing was not invented once and then spread from a single source. It arose independently in several regions, and even the picture theory that all scripts grew from pictures has a rival in the idea that cuneiform grew out of tokens used for counting. Language can be acquired without explicit teaching, while writing must be taught, which shows that writing is a cultural technology, and not a biological endowment.
Emoji bring the same questions into the present. Their meanings shift with generation and irony, so they behave like signs whose conventions are negotiated within communities. The Unicode Consortium decides which of them enter the standard repertoire, acting as a gatekeeper of a writing system, and generated or custom emoji raise the question of whether a sign can exist before a community has agreed on what it means.