I often have to explain computing concepts to non super users, and I often do it by relating computing concepts to real life situations.

I wouldn't mind seeing how other super users do it, and some really good explanations might come in handy instead of me having to wing it.

**So, how do you explain advanced computing topics to the 'normal' people? Provide some examples of some of your best 'normal people friendly' explanations!** 

*Notes: One explanation per answer, and let the best float to the top. CW turned on, since this is subjective. Also, feel free to edit my tags if you can think of better ones =)*