Neural Nets Vs. Neural nets are like the brain in that they have interconnected units which pass activity between themselves.
Some units are specific others are part of a pattern.
How similar or different they are to the brain doesn't really matter. It's how good they are at resembling the output of the brain which is important. If the output is the same then perhaps reverse engineering could be used to work out 'how' it occurs. The neural nets consist of either just an input and an output layer or these plus other layers. Using supervised learning which gives feedback to enable back propagation to strenghen connections, neural nets are able to learn.