Probably the first kind of material people wrote on was clay. TheyThe people who did the first writing dug it from the riverbanks where theythe people who did the first writing lived. The people shaped the clay into flat bricks thatthe flat bricks are called tablets. To write on a tablet theythe people who did the first writing used a reed, whicha reed is a kind of tall grass theythe people who did the first writing found nearby. The tablet had to be moist to write on itthe tablet. AfterwardsAfter they wrote on the tablet itthe tablet was allowed to dry and harden in the sun. ThatDrying and hardening in the sun made the writing permanent unless the tablet got wet again—whichgetting the tablet wet again was often done on purpose. ThenWhen the tablet was wet again the wet clay was smoothed, the writing was erased, and the tablet was ready to be used again.
Luckily for uspeople who live in modern times, thiswetting, smoothing, and erasing the tablet did not always happen. Archaeologists are scientists whothese scientist study ancient places. TheyArchaeologists have found many clay tablets with writing on them. SomeSome clay tablets are easily broken, since theythe clay tablets that are easily broken are just dried mud. But othersother clay tablets are very hard. These tablets The clay tablets that are very hard were heated to high temperatures. That is becauseThe tablets were heated to high temperatures because sometimes the buildings where ancient people stored theirthe ancient people's tablets caught fire and burned. ThisThe buildings catching fire and burning was unlucky for themthe ancient people but lucky for uspeople who live in modern times. OtherwiseIf the buildings had not caught fire and burned much fewer of the tablets would have lasted so long.
When dry clay is heated very hot, itthe dry clay turns into a much harder material. This new materialThe much harder material will not crumble. ItThis new material will not change its shape when wet. Whatever has been writtenAny writing that was written on itthis new material will not disappear.