The world wide web relies on cables to function so those cables are essential for global communication through the internet.
This video (from Commoncraft) explains in plain English how the world wide web works.
This video gives a brief introduction to the very first trans-Atlantic cable that was laid in 1858. Cables enabled communication with Europe and had a huge impact on the United States who had previously been isolated from the rest of the world.
This video explains how underwater internet cables are laid.
Click on the image for an interactive cable map of the world.
Click on the image above to access an interactive map highlighting the kind of issues that can arise when cables are damaged.