Joe looks at one of the greatest inventions of all time - the light bulb!
Newsround's running an inventions competition and to get you inspired Joe's been looking at some of the best inventions of all time.
First up is the electric light bulb - life would be difficult without it.
But it wasn't just thought of by one person - Joe's been finding out about the men who raced to be the first to make a bulb that worked and claim the glory.
Why not give inventing a go yourself and take part in Newsround's Inventions Competition?