The definition of writing

This the the representation of sound and speech in meaningful form and in graphic form on papyrus, Stone, vellum or parchment, or on similar objects.
Through the alphabet, we make a combination of letters to spell out every sound that we make when speaking. Many types of writing have evolved from cuneiform to hieroglyphics and now the alphabets.
Several kinds of media for transfer of information have evolved over the years. These include clay tablets, papyrus, stone, parchment, paper microforms and now digital medium.
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