Why is the address /ipfs/Qm... so common?

Original Question: Why is the address /ipfs/QmQmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn so common?

(discourse won’t allow this title because it’s confused by the hash.)

From @JesseWeinstein on Sun Sep 04 2016 18:26:37 GMT+0000 (UTC)

Because it is the address for the empty directory. So every time an empty directory is referred to, that will be the address given for it. It is also the default value that a peer publishes on IPNS, so you’ll see it there a lot too.

Copied from original issue: https://github.com/ipfs/faq/issues/173

From @JesseWeinstein on Sun Sep 04 2016 18:30:16 GMT+0000 (UTC)

You can verify this as follows:

mkdir an_empty_directory ; ipfs add -r an_empty_directory/

which will output:

added QmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn an_empty_directory
 0 B / 4.00 KB [-------------------------------------------------------------------------------------------------------------------------------------]   0.00%