Hi @Petr_Hajdusek that is good point. in this case the smart contract calls the school api which return the students result, but your smart contract has to inherit another smart contract that interact with external api like Oraclize, check this link for more info https://medium.com/aigang-network/how-ethereum-contract-can-communicate-with-external-data-source-2e32616ea180
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Web 1.0 was the first generation simplified Internet pages without bells and whistles.
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A smart contract on the blockchain is a self computing program with certain prerequisites for its execution expressed in the Ethereum code.
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Transactions on the blockchain are transparent to anyone to see and verify how they were triggered by the set conditions expressed in the Ethereum code.
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@kyliezz @Cryptojuice
The Discussion is for you to get used to forum discussions. The first content video starts from here ‘Ethereum and Smart Contracts Introduction’
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How did it gow? I did exactly the same… but realised at the end of the TA for programming the bot I need some JavaScript knowledge… 
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What would you say is the best way to start learning to code/develop for either an ICO or a DApp?
Greetings sir! If you want to start development from scratch the Javascript Programming for Blockchain Developers should be the first step.
After finish it, you can choose to go into Ethereum courses or take C++ Programming for Blockchain Developers, so you have a better picture and skills for any other programming course.
Bitcoin
Ethereum
Recommended
EOS
Gaming
Hope you find this useful.
If you have any doubt, please let us know so we can help you!
Carlos Z.
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Great to be here. Progressing well in my course and looking forward to learn more about Ethereum.
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@Alko89 i know this is a speculative question. But ETH is far superior to BTC. ETH has utility, use cases etc as “programmable smart contract money”. So why is the price of BTC far eclipsing ETH ?? is it only because BTC is “aged” and was the first? (disclaimer: i own both).
Hello miss, BTC is caped to 21millions top, ETH is unknown by the moment, more than 100millions of ETH on circulation by now, so basically BTC is more scarce than ETH, offcourse ETH offers a lot of use cases better than bitcoin, but ethereum is still under development, bitcoin is at production level now, work as store of value and nothing more, it have the longest chain alive so people trust more on BTC than ethereum. At least this is from my poing of view.
If you have any more questions, please let us know so we can help you!
Carlos Z.
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@thecil i forgot about the most important point. There is a predetermined supply that it will ever reach.!! great response.thx.
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Thank you Ivan, I have enjoyed the first part of my course which is Bitcoin 101. Very educative and eye opening. Now looking forward to learning about Ethereum.
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I have a question about UTXO vs. Account Model. Ivan seems to be saying that each individual satoshi can be traced back with BTC transactions, but I think that only works if all transactions have one input. If a BTC transaction have 2 or more inputs, then the concept of back-tracing individual sats in from output(s) becomes meaningless.
Also, in ethereum you could “simulate” 2 or more inputs or outputs by doing several transactions, for example send some eth from A -> C, then from B -> C, then from C -> D, then from C -> E. Then the eth from D or E cannot be individually traced back whether they came from A or B?
So I don’t see how there is a fundamental difference between BTC and Eth in terms of traceablity or privacy, except that in practice transactions in Eth have a different structure than in BTC.
For example you could consider all Eth that has a transaction history-connection to a tainted account to be tainted?
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Man you gotta love these courses!
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Hello sir, the UTXO model makes harder to track the provenance of the funds.
There are still procedures to keep track of the funds provenance of a wallet (since the blockchain is public, there will always be a way to track any wallet funds).
The Account Model is quite easy to track the provenance of a wallet/account, since you can track “from, to, quantity, hash, time” on the blockchain in a way more simple than UTXO.
Even the fact of sending funds back to yourself, means an output with a input, so you can send 1 BTC (1 input) divided for 8 persons, 0.1 BTC per person = 0.8 BTC for persons (8 outputs). The rest 0.2 BTC will be automatically sent to another address that you control from your private keys, so it counts has another output. Inputs must be spent completely, there is no way to spent like 80% of an input (0.8 BTC), this is why if you spend that 80% to persons, the 20% goes back to yourself in another address (create a new input with the rest of the funds 0.2 BTC).
From the human perspective, is quite hard to follow the track of 1 input with 9 outputs. This is when some kind of privacy comes from, since 1/9 output is yourself and 8/9 are the persons. How can you track from the outside which belongs to who?
The Account Model is quite easy to track the provenance of a wallet/account, since you can track “from, to, quantity, hash, time” on the blockchain in a way more simple than UTXO.
Basically you example said that C will receive funds from A and B, then C will sent funds to D and E right? In this case, when E or D receive the funds, they can be able to see the transaction and goes back to C historical transaction, then you can analyze the C wallet and check that it receive funds from A and B. Meaning, you can check the provenance of the funds in a very easy way than UTXO model (meaning, less privacy).
Hope this gives you a clear view of the subject, keep learning! :
If you have any doubt, please let us know so we can help you!
Carlos Z.
hello - just dropping by to say hi… super excited in learning about Ethereum!
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Hello kath7lee!
I am also starting in learning about Ethereum today. Cheers 
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cool! hello classmate
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I have a question regarding the EVM. If all nodes execute all smart contracts, then shouldnt there be a severe bottleneck pretty soon? Lets say ethereum get world adoption and there are millions of smart contracts, how would each node execute every smart contract? It’s still a physical machine that has to process everything in the end.
Maybe this is part of ethereums scaling problems and the high gas fees we are experiencing right now?
How can be a bottleneck on a decentralize computer network (meaning: computation power), every new node translate to more compute power for the entire network. A bottleneck could happen on ethereum like it was on Bitcoin years ago, too many transactions than what it can actually process every 10 minutes. So from my point of view, the only way to get a bottleneck on Ethereum nodes is that there are more transactions waiting to be processed than what the actual network can handle.
Not every node execute all smart contracts, is based on location, for example you send a transaction from your house, you are going to connect to the closest nodes you have, so those nodes will process verify and process your transaction, while there are other nodes in the network that are really far away from you that will not even notice your transaction, they will add it once it has been processed (validated) by a bunch of nodes closer to you.
High fees are part of the scaling issue at this moment, we are not ready for mass adoption if you have to pay like 10$ for a transaction amount of for example 100$ (10% of the total tx is too much for a new monetary system). But this should be fixed in Ethereum 2.0 along with other actual issues.
Hope this gives you a clear picture of the subject.
If you have any more questions, please let us know so we can help you!
Carlos Z.
Day 1 for me on Ethereum-class.
lets goo!!!
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