Hash functions are used to chain the blocks 
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Hash functions are not used the same as public key cryptography. For that the elliptic curve is used, however the public key is hashed to get the address 
- A hash function is a mathematical function that takes an arbitrary length inputted string and generates, usually a cryptographically strong (dependent on the hashing algorithm), unique, fixed length, output.
- Hash functions are used to write new transactions to the blockchain by way of PoW algorithm during the mining process.
- We mean collision resistant when different inputs to a given hash function will not produce the same output as one another.
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Good stuff thanks. What else is special about the hash function?
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- Special functions which output is really, really hard to link back to its output.
- Many things from deriving public keys to block signatures, verifying if an unspent transaction can be spent by a specific key and much more.
- Most hash functions are not really collision resistant. But it basically means that you get the same output for two or more different inputs (which is also really, really hard to achieve).
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Describe hash functions with your own words
A hash function takes a value and returns a digital fingerprint. It will return a unique output for every unique input and it should be impossible to find the input value based on an output value.
How are hash functions used in cryptocurrencies like bitcoin? (Try to research this on your own, we will cover this later in the course but challenge yourself and see if you can find information on this already now).
Hash functions are part of the bitcoin protocol where it is used to write blocks of data in the blockchain which is done through mining.
What does it mean when we say that hash functions need to be collision resistant? (We didn’t use the term “collision resistant” in the lecture, but you will easily find this on Google, we add this question intentionally to make you research information on your own, that’s how you learn best).
Collision resistant means that it should be unfeasible for the hash of 2 different input values to be equal.
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A hash function is a function that takes an input and converts it into a string of various characters, numbers, etc. dependent on what type of hash function you are using. It provides a strong measure of security, as with the output information alone, it is infeasible to determine the information that was input.
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Hash functions are used in Bitcoin to provide security for the user’s wallet, protecting their private key while still allowing transactions via their public key from one wallet to another. They are also used to build the blockchain by retaining the hash of the last block onto the current, and the current on to the next, and so on.
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A collision resistant hash means that it should be extremely rare in the instance that two different inputs result in the same output.
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- Hash functions are uni-directional functions that produce a unique output for every unique input. Just changing one bit of information will change the output.
- Hash functions are predominantly used in cryptocurrencies like bitcoin in the mining process. This is where the software goes through the process of trying to answer the “riddle” to create a new block.
- Saying that the hash functions need to be collision resistant means that it is infeasible for two inputs to have the same hash. Meaning that each individual input will generally have it’s own output.
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It’s a process of converting input of any length into a fixed size. So, the input can be any size of text, it then gets converted by some mathematical calculation called the Hash Function, and the output is the Hash Value which is a unique fixed size of alpha numeric.It’s also only one way
Hash functions secures the input so only the intended recipient can read it.
A collision is when two unique data input create two identical data output (crash!). So, it is super important that hash functions need to be collision resistant otherwise the data integrity is lost.
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1.Describe hash functions with your own words
Hash functions encrypt an input into a unique 64 characters output, creating a unique
2.How are hash functions used in cryptocurrencies like bitcoin?
Hash functions are used to write new transactions into the blockchain through mining process.
3.What does it mean when we say that hash functions need to be collision resistant?
It means that it’s hard to find two inputs that hash the same output.
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Hash functions allow inputs of varying lengths that will return outputs of fixed length. Provided the exact same input is offered then identical outputs will be repeated. Even a slight change in input will provide a completely different output - albeit one of the same length. Hash functions are one way in that you can determine an output from an input but never an input from an output.
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Bitcoin uses the SHA 256 hash algorithm to create new transactions in a unique and secure manner through the mining process. The mining process confirms new blocks in the chain but requires the tremendous combined computing power of the miners to find consensus.
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A hash function is collision resistant not collision proof. This means that potentially two different inputs could produce the identical output however this is described as infeasible as in so mathematically unlikely that it is irrelevant. Collision resistance prevents an attacker modifying the block chain.
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- A encryption of a phrase or words etc. You put something in and get some totally different out, without the possibility the reverse.
- It is used in mining where a miner have to find the hash.
- It is not possible that 2 different inputs creates the same output.
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Q).Describe hash functions with your own words
A). A hash function is a mathematical process that takes input data of any size, performs an operation on it, and returns output data of a fixed size.
Q).How are hash functions used in cryptocurrencies like bitcoin? (Try to research this on your own, we will cover this later in the course but challenge yourself and see if you can find information on this already now).
What does it mean when we say that hash functions need to be collision resistant? (We didn’t use the term “collision resistant” in the lecture, but you will easily find this on Google, we add this question intentionally to make you research information on your own, that’s how you learn best).
A). Collision resistance is a property of cryptographic hash functions: a hash function H is collision resistant if it is hard to find two inputs that hash to the same output; that is,
two inputs a and b such that H(a) = H(b), and a ≠ b.
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That a minor change of the input results in a drastic change of the output 
Hash functions are irreversible. Not the same as encryption where you encrypt data with a public key.
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A unique input is given and a unique output is hashed out. You can get an output from in input but not and input from an output. A hash function is one-way only.
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Hash functions are used as part of the block hashing algorithm which is used to write new transactions into the blocking through the mining process.
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Hash functions need to be collision resistant so that it’s hard to find two inputs that hash to the same output.
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Hash function takes data of any length performs a mathematical computation on it and returns a output of a fixed size.
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Hash functions are all part of the most recent, not yet confirmed transactions along with additional inputs , relating To the timestamp reference to the previous block.
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Collision reresistant if it is hard tofu d two inputs that hash to the same output.
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1.- It is a function that delivers an specific output for each input, this output is like a digital fingerprint of the input.
2.- The hash function are used to secure the network through “mining” and gives reward to those who have the computer power to find the appropriate hash solution.
3.- Collision resistant means that it must be infeasible to find two different inputs that have the same output
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- A hash function takes a input an return a fix length output which = hash function
2.The transaction data is hashed,when put through sha 256 algorithm then a block in the chain contains a hash of the previous block in the chain’s data an if the simplest change is made the output has changes. - If two separate inputs produce the same hash output, it is called a collision . …
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hash functions can actually be anything not just unconfirmed txs and they remain on the blockchain, they are not just a temporary thing
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