UK postcodes: The intrigue!

[Tabouli]

Ah yes, David and all ye British folk...

While we're on the subject of UK addresses, something that has always perplexed me is those double barrelled postcodes like BS23 3JL.  How do they work?  I've figured out that the 2 letter code in the first bit is an abbreviation of the county, but what's the rest?  Do they divide the county up into bits and number them?  What's with the other bit then, the suburb code?

I also notice that Canada has similar postcodes.  What's the story there?

Tabouli.


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