i don’t get it, if a word like “hi” can have a hash. can’t you put in the hash to get “hi” as an output?
if hash collision is possible by theory this should not be possible right? because if by very very very smal chance the word “cow” has the same hash, what would the output be than?? 
**wth you can actually reverse hash something my god am i over my head in here? so many questions, so little time 
**
Hi, there is no discord chat , just the forum for now… 
I know how you feel, In the beginning I so had many questions to, but I found it helpful to watch the video several times and the best thing was that often, my questions were answered in the next videos. 
I also used google a lot to search for answers to my questions. The best advise is to have patience, but learn in your own pace. Blockchain is a big topic and to understand it and be an expert takes time and dedication to learn. And when you crack the code, it will all makes sense. And that is when the real fun starts… Because then you can start to create cool stuff…
I hope the best for you, my friend… Good luck! 
Ivo
haha so true, next video, boom! i have a problem with going further if something doesn’t tick for me.
the reverse hash thing i found was the md5 hash i guess. after all the searching i have done the past hour. i know so much more now 
haha it’s awesome!!
It´s cool right? We have to search a little and do some research. But we learn so much from it. If we got all the answers in one video I think I would loose patience and not learn anything. 
Good to see your positivity. Keep it up!
And don´t be afraid to ask questions, but sometimes it may take sometime to get the answer. 
Ivo
yes, There is an IvanOnTech discord server.
(For academy students only)
Do you still need help? otherwise I can invite you to my discord voice server and help you out. It’s a bit difficult to explain all of this in text.
exactly, you learn better by doing some research yourself. Because then you will remember it much better! If someone just explains you something, the chance to forget is much higher
I learn something new every day…
Thanx for the Discord link.
Ivo
Hi ziomanzo,
Thanks for getting back. I have decided to pullback for a bit and re assess the situation. I am going to do some more reading and really get a grasp on the subject. I am not really a programmer orientated guy. Am more interested in blockchain Business and Education, but I am aware that I need at least an overview of the mechanics of Programming to tie it all together. So for now I am pulling back a bit. Thank you for the offer to explain, maybe a bit down the road I can contact you and get a bit deeper into it. Regards Dietmar
this topic about functions is not that hard once you know what it means. If you want I’ll explain it to you on a voice server. You don’t have to be a programmer!
PART 1
IBM uses private blockchain solutions like hyperledger. It’s an open source private /public blockchain (DLT). There are many flavors of hyperledger, like Hyperledger Fabric. It provides a modular architecture. You have certain types of different nodes with different roles. (peer nodes, endorsing nodes, membership services providers for certificate and authenticate the members. So it’s not permissionsless like open networks like bitcoin and ethereum. Cool thing about Hyperledger is that’s it’s very modular. you can plug and play different consensus algorithmes ect… It’s usually used by a small consortium of couple bussinesses to have a private blockchain like database (DLT).
It’s if course more vulnerable than open networks where you have much more nodes to verify consensus rules. You can compare open and private networks a bit like the internet vs intranet.
Part 2
Blockchains like Ethereum have a way to modify variables in a smart contract. Everyone can verify the changes at any moment. But every ETH transactions are always immutable and can’t be changed. Only the variables in the smart contracts can be changed by authorized users to change the state of the smart contract. For example, you can code a database of users that can be modified. but once you send a transaction to modify a variable, The transaction itself is irreversible. Only a new transaction can change this variable again.
PART 3+4:
When a new block is created by a miner, it has to have certain elements in it to be a valid block.
blockstructure:
magic number
blocksize
blockheader
transaction counter
all transactions you want to include from the mempool.
So a miner will pick transactions from the mempool to include in the block.
the hash of previous block wich makes it cryptographical linked together, so that it’s impossible to change data in previous blocks withouth breaking the link.
Miners need to hash this block and make sure that the hash of the entire block is low enough to be valid and accepted by the network. (lower than difficulty target wich will need to be a number of leading zero’s) if you check block explorer, you will see that every hash of a block starts with a number of zero’s. You know that hashing will produce a random looking number that probably doesn’t have the right amount of zero’s in front. so miners will add a random number in a block (nonce) to make sure that the block hash is low enough. off course, they need to keep trying to hash the block with a different number (nonce) until they finally find a nonce that produces a low enough hash.
When they finally found a nonce that produces a lower than target hash, their block is valid and can be propagated through the network and get the blockreward + all transactions fee’s.
PART 5
You never expose your private key. you sign the transaction with a digital signature that is unique for this transaction and it proofs that it can only be generated from your private key without exposing the private key itself.
Digital signatures in bitcoin (simply explained)
important bitcoin terminology explained by Andreas Antonopoulos
Andreas Antonopolis going in dept about locking scripts and transaction verification
Great content from links provided to further understand how to use hash functions to create private key and public keys. Clear understanding of how to create signature and secure keys through using sha-256 and RMD160 to compress alpha-numeric in order to look pretty and user friendly but highly secure. 
Cryptography is encrypting and decrypting information that help participants to transact or communicate information.
By the way what is SHA and RMD stand for? @ivanontech
SHA = Secure Hashing Algorithm
https://en.m.wikipedia.org/wiki/Secure_Hash_Algorithms
RIPEMD (RIPE Message Digest)
https://en.m.wikipedia.org/wiki/RIPEMD
Hello everybody, I’m totally a newbe. Quick question regarding the dapp programs that can act on results that happen in the real world; how exactly would these events or results be verified?
Thanks!!#
I’m sorry but I don’t fully understand your question.
This section is about hash Functions and Cryptography.
hi, thanks for your reply.
Was referring to this segment:
bitcoin-101/categories/1689612)
Blockchain 2.0 - dapps & smart contracts
A dapp is a combination of smart contracts on the ethereum nework right thus how can it act on results that happen in the real world; how exactly would these events or results be verified?
Hope this clarifies it and thank you.