What Does it Mean to be ‘Digital’?
On a simple
level, a digital system is just one that works with discrete states. Digital
computers are designed around electrical circuitry that has just two states:
fully on and fully off. We typically associate these states with the binary
values 1 and 0. Once you have such a setup, you can easily represent richer
values - such as the price of a plane ticket - by using the state of a group of
on/off memory circuits.
However,
all digital systems are physical. If we take physical nature to be essentially
‘analog,’ then we need to say that all digital systems are also analog.
So, to
be digital is really a design choice, not unlike the choice one would make
between clockwork and hydraulics when deciding how to achieve a specific task.
What
distinguishes digital systems from all others is that they are designed to
reliably interpret analog properties in discrete ways. For example, a
bit of memory in a digital system will only be read as ‘on’ or ‘off’ by the
reading circuitry because of its electrical design.However, the memory circuit itself will have variable analog electrical
characteristics since it’s a physical/analog device - a bit like a battery.
Some see
digital systems as special since they deal intimately with ‘pure’ information
and absolute states, and wonder if this could mean they are somehow connected
to the divine. If this is the case, digital systems might be a place where we
would expect to see divine activity. However, since digital systems are
designed to operate in a thoroughly deterministic, reliable - even
fault-tolerant manner - they are probably the last place we should expect to
see such activity.
Email
link | Printer-friendly | Feedback
| Contributed by: Adrian
Wyard
|
