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1. Introduction to Adders

If you are at all familiar with computer programming (and you should be if you are doing this A level course), then every programming language can tell the computer to do this:

$$ x = 1 + 2 $$

In other words, command the computer to add two numbers.

But how does the machine actually do this?

The answer, is that it has to use a certain combination of logic gates within the CPU to physically add two numbers and get the answer.

The circuits in question are called the 'half-adder' and the 'full-adder'.

This section will describe their operation.


Challenge see if you can find out one extra fact on this topic that we haven't already told you

Click on this link: What is a half adder