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FEED-BACK & AUTOMATION
For hundreds of years there have been many systems that worked
automatically - that is they worked by themselves without the need for
people to control them. There were water systems that made sure that crops
got enough water using a network of weirs. Others were mechanical
systems like clocks.
All these systems were around long before electricity had been understood.
Well designed mechanisms would make the large bell chime on the hour
every hour. While still more complex parts might control moving figures that
came out, such as a cuckoo or a line of figures dancing to music.
The first computers were also mechanical. They were very large and
complex and could add, subtract, multiply and divide. They were like great
big adding machines but they could also make decisions based on a simple
set of rules.
We all have to make many decisions in our lives. Decisions may depend on
more than one thing at once. Each decision on its own is simple - if this
happens then I will do that - but taking them all together it can be quite
complicated! A computer only succeeds by dealing with every simple
decision before it moves on to the next - but it does this at great speed
which is why they appear to be so clever! - a bit like Logiblocs do today!
Breakthroughs in electronics have reduced the size and weight of computers
dramatically. The power of computers has grown enormously also. So it is
very easy for us to take all the sophisticated software and systems that we
use for granted. Logiblocs can help us to understand the simple elements
that make automatic systems work.
