The recent post on the Google blog about an update to the search algorithm is an excellent example of how to explain technology:
  1. No apologies or "I will not bother you with the detail", or "this is kind of complex and only an engineer (read someone more intelligent than you) will understand". No instead, explain things clearly, but without oversimplifying.
  2. A simple graphic supports the verbal/written explanation
In case you missed, an earlier post on how Google uses cartoon characters to explain why its Chrome browser beats the competition.