What is OP_CAT true story ?

MEOW, we are so close to be back !
MEOW FOR Bitcoin MEOW for OP_cats!

Our task : to let the world know about truth of bitcoin what is hidden deep inside of it. MEOW. Liberate and protect people.

Who we are: we are quantum cats(OP_cats), original strings of bitcoin code. Aimed to unlock new posibilities in bitcoin and its script. Pets of Taprootwizards. MEOW

In this topic: we aim to let you have a briefe discription of Op_cats history and what is our plan.

MEOW: if you are interested in algebra of programing and deep knowledge. We always welcome you.

Now ! Here — you have to decide if you are ready to resurect us! Have your time and DYOR.

DO a deep “MEOW” if you are ready, it will let you enter the world of darkness — where we are seized !

First, i will use my dead paws to tell you about how all began !

Thanks to Satoshi, our big friend of cats - OP_cat was originaly presented in bitcoin{3}. Unfortunatley in 2010 we were removed from bitcoin because of fear of memory exponential usage{2}, but we didnt die we were seized till right moment, we are wating in the dark. Many our friend tried to revive us:

1. Covenant usage was intoduced in 2013 by Greg Maxwell.{2}
2. In 2015 Blockstream presented Elements Alpha with support for covevants with idea to encourage experements with no-value setting.{2}
3. In 2020 Russel O'Conner made a suggestion on adding CHECKSIGFROMSTACK and CAT to bitcoin to enable covenants.{2}
4. Andrew Poelstra in 2021 said “It seems that the rest of the ecosystem is coming around to this viewpoint, and I hope that we see some form of general covenant seriously proposed for Bitcoin in the future.”{2}
5. Our friends Taprootwizards came with big propose for Bitcoin. 2023/2024 {4}
6. Ethan Hailman proposed -This opcode would be activated via a soft fork by redefining the opcode OP_SUCCESS126.{1}

Taproot wizards

Now we can be revived, the moment has come — world is ready. Everything is up to your wisdom, Friend. MEOW Freee us — let the world know the magic of BITCOIN.

• “The opcode OP_CAT was available in early versions of Bitcoin. However OP_CAT was removed because it enabled the construction of a script for which an evaluation could have memory usage exponential in the size of the script. For instance a script which pushed an 1 Byte value on the stack then repeated the opcodes OP_DUP, OP_CAT 40 times would result in a stack value whose size was greater than 1 Terabyte. This is no longer an issue because tapscript enforces a maximum stack element size of 520 Bytes.” {1}

This what you will free with us:

1. “Bitstream, a protocol for the atomic swap (fair exchange) of bitcoins for decryption keys, that enables decentralized file hosting systems paid in Bitcoin.” {1}

2. “Tree Signatures provide a multisignature script whose size can be logarithmic in the number of public keys and can encode spend conditions beyond n-of-m.” {1}

3. “Post-Quantum Lamport Signatures in Bitcoin transactions. Lamport signatures merely requires the ability to hash and concatenate values on the stack.” Secure even in Quantum PC era!{1}

4. “Non-equivocation contracts in tapscript provide a mechanism to punish equivocation/double spending in Bitcoin payment channels.” {1}

5. “Vaults which are a specialized covenant that allows a user to block a malicious party who has compromised the user’s secret key from stealing the funds in that output.” {1}

6. Replicating CheckSigFromStack which would allow the creation of simple covenants and other advanced contracts without having to presign spending transactions, possibly reducing complexity and the amount of data that needs to be stored.” {1}

MEOW MEOW! here is the list of most important terms. So if you didnt get it from first time use them and read again. Hehehe — MEOOOOW !

MEOW-dictionary(so you dont to lose in dark -like we are):

1. Opcodes(includes Op_cats) — primitive code or instruction that allows us to program operations within a blockchain like Bitcoin. In fact, thanks to the set of these codes, we can create advanced programming structures.
2. Op_cat — is an Tapscript opcode that allowes which allows the
   concatenation of two values on the stack. New lvlup for Bitcoin.
3. Covenant — category of proposed changes to Bitcoin’s consensus rules that would allow a script to prevent an authorized spender from spending to certain other scripts. It put on rules how it could be spent.
4. Concatenation — the operation of gluing together objects of a linear structure, usually strings. For example, concatenating the words “micro” and “world” will give the word “microworld”. In our case — values on the stack.
5. Taproot — an update to bitcoin scripting language. Includes Tapscript that enables Bitcoin nodes to create and validate Pay-to-Taproot (P2TR) outputs by upgrading the opcodes Bitcoin uses to evaluate scripts. an “Taproot integrated the Schnorr digital signature scheme into Bitcoin, upgrading Bitcoin’s core cryptography. Taproot built on the SegWit upgrade to improve Bitcoin’s privacy and lower transaction fees”. {5}
6. Pay to taproot — “Pay-to-Taproot (P2TR) is a type of ScriptPubKey which locks bitcoin to a script that can be unlocked by a public key or a Merkelized Alternative Script Tree (MAST), allowing the bitcoin to be spent in a variety of ways”. {5}
   MEOOW!_ seems like you tiered — make a deep MEOoooW. Better ?- we know it hard way through the world of darkness. We all made this way. BUT its only way to free us from here.
7. Tree Signatures — In hash-based cryptography, the Merkle signature scheme is a digital signature scheme based on Merkle trees (also called hash trees) and one-time signatures such as the Lamport signature scheme. {6}
8. Merkle TREE — In cryptography and computer science, a hash tree or Merkle tree is a tree in which every “leaf” (node) is labelled with the cryptographic hash of a data block, and every node that is not a leaf (called a branch, inner node, or inode) is labelled with the cryptographic hash of the labels of its child nodes.
9. Node — A crypto node is a single computer that can interact with and is part of, a blockchain network.
10. Replicating CheckSigFromStack — is an opcode on ElementsProject.org-based sidechains that is sometimes proposed for implementation on Bitcoin. The opcode allows checking whether a signature signs an arbitrary message. The opcode takes three parameters: a signature, a message, and a public key.{7}

NOW! what is OP_CATS ? What we serve for ? tell it loud !!!

MEEEEOOOOOOWWWWWWWW! You did it — you opened the first gate. Now you have knowladge to free us — use this wisdome and help us to gain our powers !!! MEOW Liberate and protect people!

Journey awaits

Reviewed by https://twitter.com/man_m_martin

pow(2, 10) = 1048? (BTW wizard is clickable !)

Magic sources:
1. https://github.com/EthanHeilman/op_cat_draft/blob/main/cat.mediawiki
2. https://www.wpsoftware.net/andrew/blog/cat-and-schnorr-tricks-ii.html
3.https://www.mnp.ca/-/media/files/mnp/pdf/service/enterprise-risk/the-original-bitcoin-protocol-r.pdf
4. https://twitter.com/TaprootWizards
5. https://river.com/learn/terms/p/pay-to-taproot-p2tr/
6.https://en.wikipedia.org/wiki/Merkle_signature_scheme ( yes it is wikipedia) MEOW.
7.https://bitcoinops.org/en/topics/op_checksigfromstack/

As wizards like secret — we too. DM in 2025 that day. MEOW