Connection to the world of hardware

Connection to the world of hardware

Internally, computers represent all information using the binary number system.
Why? Electronic devices that are based on only two easily distinguishable states are cheaper and more reliable than devices based on more than two states.
It doesn't matter if the two states are 0 and 1, or "off" and "on", or "closed" and "open", or "low" and "high", or whatever.
All that matters is that the two states be distinguishable and stable.

To get some practice with conversions between decimal and other base systems, see this handy demonstration of number conversions. There is also a graded exercise on binary/decimal conversion.