A youth makes his homemade robot walk in 1955.
A youth makes his homemade robot walk in 1955. - 
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For the next installment in the BBC’s Justin Rowlatt's micro-scopic look at the economy: element number 50 Tin; or symbol "Sn" on the periodic table.

So perhaps tinfoil isn't the sandwich wrap of choice. What does it matter?

"Amazingly, tin is actually the glue that holds the modern world together," says Rowlatt. "Tin still has an absolutely crucial role in the world."

Tin is also used in the float glass making process. This has made sheet glass making less labor intensive, cleaner and safer.

Rowlatt says tin is used because it is relatively abundant and cheap.