Communication of ideas

Communication of ideas is at the centre of civilisation. It needs written records. Most of our records in the modern age are on paper. Though writing was invented very early, paper is a more modern invention.
For long in history, people transferred ideas through speaking and listening. Then there came the art of writing. But to record thoughts in writing was difficult. Writing material was not available. People used surface of stone, metal, wood, bark, leaves, etc for writing. Those things were not easy to carry. Then for ages, people looked for easy writing materials. Finally, Paper was invented in china in 105AD. Before paper age, knowledge was very restricted. Can you think of that time? There were very few books in the world. May be, they were written on stone or on heavy wood plunks or on metal sheets. Suppose, one page was a heavy stone block. So, think of a hundred page book! In our age, you can carry the entire world of knowledge in digital from in your laptop bag. You can even carry a huge volume of paper encyclopedia. But who could produce and carry tons of heavy stone books and documents in those paperless days? In fact, paper has made publication and the spread of knowledge and information easy. So, you can see how paper has changed our life.