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Author: 2color

docs/concepts/content-addressing.md

@@ -11,6 +11,8 @@ For a deep dive into how Content Identifiers (CIDs) are constructed, take a look
 
 [[toc]]
 
+## What is a CID?
+
 A _content identifier_, or CID, is a label used to point to material in IPFS. It doesn't indicate _where_ the content is stored, but it forms a kind of address based on the content itself. CIDs are short, regardless of the size of their underlying content.
 
 CIDs are based on the content’s [cryptographic hash](hashing.md). That means:
@@ -20,7 +22,7 @@ CIDs are based on the content’s [cryptographic hash](hashing.md). That means:
 
 IPFS uses the `sha-256` hashing algorithm by default, but there is support for many other algorithms. The [Multihash](https://multiformats.io/multihash/) project represents the work for this, with the aim of future-proofing applications' use of hashes and allowing multiple hash functions to coexist. (If you're curious about how hash types in IPFS are decided upon, you may wish to keep an eye on [this forum discussion](https://discuss.ipfs.tech/t/who-decides-what-hashing-algorithms-ipfs-allows/6742).)
 
-## Identifier formats
+## CID versions
 
 CIDs can take a few different forms with different encoding bases or CID versions. Many of the existing IPFS tools still generate v0 CIDs, although the `files` ([Mutable File System](file-systems.md#mutable-file-system-mfs)) and `object` operations now use CIDv1 by default.