Cryptocurrency is a digital currency using cryptography. Cryptography is a security process for ensuring that transactions are safe. It came from the hidden text of The Greek.
An instance example of cryptography in history is that cryptography was used for communication in Caesar and Enigma machine. A simple way to explain it is “A safe communicate method in an unsafe environment”.
Modern cryptography is super complicated and is one important part of the internet. Whenever we access a website, we have to use cryptography, and whenever we send an email, we have to use cryptography. This technology had been improved and used for a period of time. However, it was not until Satoshi Nakamoto this technology reached a new level. With his intelligence, Nakamoto combined it all together as a car is in need of wheels.
Bitcoin is made by a combination of the breakthrough in cryptography and computer sciences which is proof of work and many other techniques.
One of the most important bits of Bitcoin currency came from a part of cryptography with Elliptic Curve and digital signature.
What is Curve Cryptography? How to make a digital signature work in Bitcoin?
This is a place that you will get your address and a public key that comes from your private key. You can create a public key from a private key, but you cannot create a private key from a public key. This is the secret behind Bitcoin which makes Bitcoin a real currency.
The fact of lacking double paying ability comes from blockchain and decentralization of transaction verification point. This makes users can use a transaction only one time. And this is the way that makes Cryptocurrencies are trustable.