Why are blocks hashed?

[MoMoneyMonetarism]

I think I understand that addresses are hashed to compress massive coprimes.

I think I understand that transactions are hashed for the same compression motivation but also to keep the encrypted content more random thus more secure.

I can't figure out why blocks are hashed and can find no explicit motivation in the Satoshi paper, wiki, or here.

Are blocks hashed only to slow verification thus reward release rates?  If not, why?

Thank you so much in advance!

[1538087642]

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[1538087642]

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[1538087642]

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[kjj]

Transaction and block header hashes are used as identifiers.

[t3a]

Yes, a blocks hash must be below a certain value to receive the block rewards. Along with that, the next block has the previous blocks hash inside of it, confirming that that is the previous block.

[GhostInTheBlockchain]

Are blocks hashed only to slow verification thus reward release rates?  If not, why?

No.  The block hashes link the blocks together into a chain.  The hash of the previous block is included in the data that forms the next block and therefore contributes to the hash of the next block.  This, combined with the proof of work part of the algorithm, causes the chain of blocks to act as a kind of distributed time-stamping service that proves when (and that) each bitcoin transaction took place.  See the 'Proof-of-Work' section of the Satoshi White Paper for more details.