what do you think was the best invention ever?

Toilet tissue of course. Otherwise, what are we going to use to clean our a$$?

The dicovery of alternating current by Tesla

I think the most important invention is electricity. Electricity figures everywhere in our lives. Electricity lights up our homes, cooks our food, powers our computers, television sets, and other electronic devices. Electricity from batteries keeps our cars running and makes our flashlights shine in the dark. Although Ben Franklin, he made many important contributions. Later scientists, like Michael Faraday and Thomas A. Edison, continued to study electricity using many of Ben's ideas. Even today, scientists are still studying electricity and learning more about it.

related resource: invention ideas

The light is so far the best invention that was ever invented. We the light we can see clearly, we can respond easily, we can write, we can talk, we can eat, we can relax, we can shout, we can do things, we can cook, we can wash clothes, we can write the way I am responding to this discussion, for it there was no light there will be no computers, no mylot and no one to respond like this...