![1.png](https://cdn.steemitimages.com/DQmfLE8tPC4yVnarqRT4nz4DnZ6R74cc2raLqoBbS6xivqR/1.png) 3a) What is a Cryptocurrency? b) What is Cryptography and how does it make cryptocurrencies secure? c) Explore the Steem Genesis Block and Sign in as proof of completion. ### What is a Cryptocurrency?

Cryptocurrencies are form of digital assets base on network which has lot of computers. This is not a type of traditional currency type.This exits in a decentralized manner which governments and central authorities cannot control. Cryptocurrency transactions are based on encryption method to make the transactions secure.Cryptocurrencies have good qualities in transparency , portability and inflation resistance. But also got some blames like it disturbs finance and law of many countries and using for illegal activities and exchange violations. "Bitcoin" was the first blockchain based cryptocurrency which was launched in 2009. And it's still the most famous cryptocurrency type. Now then are are lot of type of Cryptocurrencies like,

• Bitcoin • Ethereum • Litecoin • Monero • Ripple • bitshares • NEM • Bitcoin Cash • Stellar • Ethereum Classic • Zcash • Dash • Dogecoin

• Lisk • siacoin • Factom • 0x • OmiseGO • Viacoin • burst • Ardor • Augur • blackcoin • vericoin • peercoin • nexium ### What is Cryptography ?

Cryptography is the method of sending data between two or more people. This is very secure method and third parties cannot read it and stole them. Cryptography can be divide into 3 different types (Secret Key Cryptography, Public Key Cryptography and Hash Functions) While the sender entrypte the message by using the Public Key , the reciever have to use Private Key to decrypt to read it. So no third party can read the content. So the Cryptography make transactions of cryptocurrencies anonymous & secure.

### How does it make cryptocurrencies secure?

This method has a technology which include Public Key - Private Key encryption. Cryptography in Cryptocurrency helps to do transactions between completely 2 strangers without 3rd party like Bank or exchange merchant.

The Public Key in wallet may allow user to do Only transmit and receive the tokens. While the Private Key in wallet may allow user to do access to their wallet assets and do the transactions.

### Explore the Steem Genesis Block and Sign in as proof of completion. * The Steem Genesis Block can access through https://steemworld.org/ * Go to https://steemworld.org/ website ![3.png](https://cdn.steemitimages.com/DQmfBVZ9yaFUP7atei3j1roXdRQLMutiisFtbjhpXBgDucn/3.png) * Click On "Block Explorer" ![4.png](https://cdn.steemitimages.com/DQmbHfcj2hqn7wvcPjXp4ZoqaZGcoXzjDDMp5EaEmzog5mk/4.png) * Type "1" as Block Number ------> Click OK ![5.png](https://cdn.steemitimages.com/DQma7C2NyTPj1ke3uBXFDFcWzaHgnQbYXJq3A7L77URGgVg/5.png) * Then it will load all information about Genesis Block ![6.png](https://cdn.steemitimages.com/DQmZhvC9jBWCFZ2RsxhkMd46pvJp83aCZUao1zp6cwCFXwd/6.png) Timestamp : 2016-03-24, 21:35:00 Block Id : 0000000109833ce528d5bbfb3f6225b39ee10086 Previous Id : 0000000000000000000000000000000000000000 Signing Key : STM8GC13uCZbP44HzMLV6zPZGwVQ8Nt4Kji8PapsPiNq1BK153XTX Witness : initminer25 * Click on Sign In ![7.png](https://cdn.steemitimages.com/DQmXN4yYnwjwshpEroVD7a3ZRZvBSbGvnyeEGRizsdoGrcM/7.png) * Use Private Posting Key and Sign In ![9.png](https://cdn.steemitimages.com/DQmfGnAjHaUEoNz1bGhNHVsnM8BhD3TsVSXPDvpYxybnzbb/9.png) * Here you can see your user name after successfully Sign In ![11.png](https://cdn.steemitimages.com/DQmb5xPAA8iASoXtdQygKjSJWrxuZsgCk3vn6Cdq99uBLvy/11.png) I hope you all learn more about "The Genesis Block" from this post. Thank you Cc:- @steemitblog @steemcurator01 @steemcurator02 @awesononso #academys4-intro03 #cryptoacademy