This clip explains that the product of any number multiplied by zero is zero.
This clips explains that every digit makes sense in two different ways at the same time. It makes sense according to which digit it is, which is known as face value, and it makes sense according to where we decide to put it, which is known as place ...
This clip talks about whole numbers and the system that was developed so that they could be written and spoken. It's known as the system of decimal numerals, based on symbols called digits.