The Scot, John Napier, invented these strips (originally made from bone) about 400 years ago to help calculate multiplication and division.
This is what they looked like:
Can you work out how to use Napier's bones to find the answer to
24 x 6?
How about 461 x 4?
Now try 8931 x 6.
Can you work out how you would use them to calculate the product of 3541 and 768?