# What is cryptography?

In this digital era, many of us benefit from encryption multiple times a day without ever realizing it.

When you visit a secured website such as your bank’s website or an online retailer, cryptography is used to keep your private information protected. Used to timestamp electronic documents and to transfer money electronically, cryptography is also one of the key elements in blockchain technology.

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Check out a brief history of cryptography below.

## Using cryptography

Even though it may be easy to solve a simple algorithm that uses letters, numbers and even symbols, modern cryptography will often require the help of complex mathematical functions. Cryptography is nothing new and it has been around since ancient times. The invention of the computer led to more advancements in cryptography and more uses for encryption in the modern world..

There are two cryptography techniques used in the process of encrypting and decrypting data:

### 1. Symmetric cryptography

Also known as conventional cryptography, symmetric cryptography requires the sender and the receiver of confidential information to share a key. The key is the item of private information that is used to both encrypt and decrypt data.

It is important that the process the two individuals use to agree upon a key is a secure network or medium to guarantee that their secret key remains a secret to all others. Until the two parties agree upon the key, they have no way to share their information with one another in private.

### 2. Asymmetric cryptography

Also known as public key encryption, asymmetric cryptography helps solve the key exchange issue by using two keys instead of one. Either key may be used to encrypt data, and the encrypted data can only be decrypted by using the other key.

## Common methods

There are several different methods of encryption, and the most commonly used are shared secret key encryption and public key encryption.

### 1. Shared secret key encryption

In terms of cryptography, a shared secret key encryption is a key that only a select group of people know. It can include anything from passwords to PINs and pass phrases. A good example of a shared secret key encryption is the password for company software that is used by multiple employees or a door PIN that allows a group of people to have access to a building.

### 2. Public key encryption

Public key encryption is a system that uses two keys that are mathematically related, but not necessarily identical. There is a public and a private key. Each key performs its own unique function. The public key is used to encrypt, and the private key is used to decrypt.

This method is often used in various business applications, especially with digital signatures. When a document or form is signed digitally using the individual’s private key, it can be verified by the same individual’s public key.

## Understanding blockchain technology

Blockchain technology was invented by a group of people known as Satoshi Nakamoto. This ingenious new technology is changing the way that we share digital information online. But what is blockchain technology and how does it connect with cryptography?

First, make sure you completely understand blockchain. Check out the video below by the Institute for the Future.

Blockchains allow digital information to be shared on the web, but not copied. It was originally developed for use with the digital currency, Bitcoin. However, Satoshi Nakaoto found a brand-new use for it by protecting shared documents. For example, imagine an Excel spreadsheet has been duplicated many times across various computers in your office network. But what if the network was capable of regularly updating this spreadsheet? That is a simple explanation of what blockchain technology is.

The information on the blockchain is saved and continuously updated on a shared database. This can be very beneficial because the data isn’t saved in one single location and it is easy for those who need access to it to obtain it.

There is no central version of the data for a hacker to steal or change. Yet at the same time, the data is accessible to anyone online.

## Final thoughts

Modern cryptography can help all types of professionals keep personal and confidential information secure. It can also be beneficial to keeping cryptocurrency secure.

Bitcoin uses blockchain technology to ensure that cryptocurrency cannot be copied or stolen. Blockchain technology allows two individuals to make a transaction directly with one another with no additional fees. Once the cryptocurrency data is verified, it becomes permanent and impossible to edit by hackers.

Cryptography can ultimately be thanked for changing the way we share information online, as well as doing its part to make the internet a safer place to be.