When was writing invented? The oldest system of writing is believed to be cuneiform, which originated more than 5,000 years ago in ancient Mesopotamia, modern day Iraq.
In the earliest form of cuneiform, objects were represented by pictures drawn on soft clay tablets. It is thought these pictures evolved from even earlier marked clay tokens which were used to count goods in trade. The clay tablets hardened in the sun and could not be reused, so they were thrown away. Because they were baked, many of them survived and archaeologists have so far unearthed more than 5,000.
The most important development in cuneiform came when the pictographs were read according to the pronunciation of the objects shown rather than the object itself. This is called the rebus principle, which is often used in word puzzles. For example, a picture of an eye, a bumble bee and a leaf could be read as 'eye-bee-leaf' or 'I believe'.
In the 3rd millennium BC, cunei form came to be written in rows from left to right, a convention used by most written languages to this day. The cuneiform system lasted until the 1st century AD.
While the Mesopotamians were developing cuneiform, the Egyptians were inventing hieroglyphics.
A bit later, between 2800 and 1900 BC, the Harappa civilisation along the Indus River, in what is now Pakistan, had a developed script with up to 500 characters.