[Blog](/blog)

Show links

Resources

[Blog](/blog)

[Breaches](/breaches)

[eBooks, reports, & more](/resources)

[Events](/events)

[News](/news)

[Cybersecurity](/category/cybersecurity)

Show links

Categories

[Attack Surface Management](/category/attack-surface-management)

[Company News](/category/company-news)

[Compliance and Regulations](/category/compliance-and-regulations)

[Cybersecurity](/category/cybersecurity)

[Data Breaches](/category/data-breaches)

[DevOps](/category/devops)

[Human Cyber Risk](/category/human-cyber-risk)

[Risks and Vulnerabilities](/category/risks-and-vulnerabilities)

[Third-Party Risk Management](/category/third-party-risk-management)

[Vendor Risk Management](/category/vendor-risk-management)

[What is Cryptography? And How You Can Secure Your Data](/blog/cryptography)

Publish date

December 1, 2025

{x} minute read

# What is Cryptography? And How You Can Secure Your Data

[Get a demo](/contact-sales)

[Free trial](/demo)

[Download the PDF guide](/resources/complete-guide-to-data-breaches)

[Free trial](/demo)

Written by

[Kyle Chin](/team/kyle-chin)

Cybersecurity Writer

Kyle's work has been featured in law publications, academic institutions, and government bodies.

Reviewed by

[Phil Ross](/team/phil-ross)

Chief Information Security Officer

Phil is a Forrester Zero Trust Strategist leveraging decades of experience in enterprise cybersecurity architectures.

Table of contents

eBook

A Complete Guide to Data Breaches

Free resource

### A Complete Guide to Data Breaches

Learn how to avoid a costly data breach with a comprehensive prevention strategy.

[Download now](/resources/complete-guide-to-data-breaches)

Cryptography is the practice of securing and transmitting data and information in a form that only authorized parties can understand. [Encryption](https://www.upguard.com/blog/encryption) processes encode the original message using crypto-mathematical concepts, and rule-based calculations called algorithms to protect against [malware](https://www.upguard.com/blog/malware) or [cyber attacks](https://www.upguard.com/blog/cyber-attack).

The word comes from the Greek word "kryptos," meaning 'secret' or 'hidden.' The literal translation for cryptography is "secret writing." It comes from the study of cryptology, the art of breaking codes or ancient hieroglyphics and solving them.

Data encryption is one of the most important tools for building secure communications, networks, and system infrastructure. By following the pillars of [information security](https://www.upguard.com/blog/information-security), cryptography ensures that no unauthorized parties or threat actors can access confidential data. It's an extremely specialized field of [cybersecurity](https://www.upguard.com/blog/cyber-security) that requires expert knowledge to implement. From web browsing to sending emails to credit card or cryptocurrency transactions, cryptography helps secure [sensitive data](https://www.upguard.com/blog/sensitive-data) in every aspect of our lives.

## How Does Cryptography Work?

The best way to understand simple cryptography is to look at one of its earliest forms, the Caesar cipher. Julius Caesar used it to encrypt confidential correspondence between him and his officials.

Caesar encrypted his messages by changing the order of the alphabetical letters. In order to decrypt the message, the intended recipient would have to substitute the written letter for the corresponding letter in the original message to decode the encrypted message. This is called a substitution cipher.

We can break this description into two cryptographic elements: the algorithm and the key. The **algorithm** is simple and involves substituting a letter with another from later in the alphabet. The **key** is how many spots in the alphabet you must move to find the original letter or set of letters in a word to decrypt the message. The key was three in this version of Caesar cipher, in which case you would substitute the letter D for letter A, H for E, and so on.

## Modern Cryptography

Modern cryptography exists through the combination of advanced mathematics, computer science, communication, and engineering processes. Computers and operating systems use complex [encryption](https://www.upguard.com/blog/encryption) methods to encode messages so only authorized parties can see them. The message, or plaintext, is converted into ciphertext using an encryption algorithm that generates an encryption key. In order to read the message, the recipient must use a decryption key, which turns the ciphertext back into plaintext.

Cryptographic algorithms (or ciphers) play a large role in [data security](https://www.upguard.com/blog/data-security) because they are used to generate cryptographic keys and digital signatures, protect payment transaction protection, secure web browsing, and message authentication.

[*Learn more about encryption here.*](https://www.upguard.com/blog/encryption)

## What are the Different Types of Cryptography?

Three main types of cryptography or cryptosystems can be used to protect data transmissions:

### 1. Symmetric Encryption

In symmetric cryptography, both the sender and receiver use the same private key to encrypt and decrypt the message simultaneously. Without the key, it is nearly impossible for hackers to intercept and decode the message. This method is also called secret-key or private-key cryptography because only a single key is used during the process.

There are two main types of symmetric key cryptography:

* **Stream Cipher** - A streaming algorithm encrypts plaintext bit-by-bit, a single bit at a time. The same plaintext bit will encrypt to a different bit with every successive encryption. Examples of stream cipher algorithms include BLOWFISH, A5, and RC4.
* **Block Cipher** - A block cipher applies a deterministic algorithm to encrypt a block of plaintext instead of encrypting it bit by bit. The system keeps the blocks in memory while waiting for complete data encryption. Some of the most important block cipher algorithms include Triple DES (Data Encryption Standard), AES (Advanced Encryption Standard), and Twofish.

However, one of the risks of symmetric key encryption is that if the shared private key is compromised, the whole system for securing data becomes compromised.

### 2. Asymmetric Encryption

Asymmetric cryptography helps eliminate the key sharing problem by generating two different keys — a private key and a public key. Also known as public-key encryption, this method uses a public key to encrypt the message, while the private key strictly decrypts the message.

To understand it better, think of the public key as the key to your mailbox. It opens the mailbox just wide enough to drop letters. You can share this key with anyone who sends you letters so they can drop the letters into your mailbox. Only you have the private key, which you use to get the letters out.

The sender of the message can use the recipient's public key to encrypt a message safely because the only corresponding private key that can decode the message is in the recipient's hands.

Examples of public-key cryptography or asymmetric-key cryptography include Diffie-Hellman key exchange, RSA (Rivest–Shamir–Adleman), DSA (Digital Signature Algorithm), ECC (elliptic curve cryptography), and post-quantum cryptography.

### 3. Hash Functions

Hash functions use a one-way encryption algorithm, known as a hash value, to encrypt plaintext into ciphertext. Once you convert plaintext to the hash, you cannot revert it to plaintext. For any given hash function, no two plaintexts will yield the same hash.

Hashing algorithms help ensure confidentiality and confirm data integrity. For example, if you received a message along with its hash, you can run the hashing algorithm on the message to verify if anyone interfered with the message during transit. If the hash differs from the one sent with the message, you can assume that someone has compromised the message.

Examples of commonly used hash functions include checksum functions, cryptographic hash functions, and cyclic redundancy checks.

## Cryptography in Cybersecurity

Computers communicate with each other daily via direct connections, which creates the need for strong [data security](https://www.upguard.com/blog/data-security). Modern-day applications of cryptography are seen in e-commerce, banking systems, military communications, and basic user-to-user messaging.

Implementing [data encryption](https://www.upguard.com/blog/encryption) and cryptographic processes achieve the following objectives of information assurance and information security:

* **Confidentiality** - Unintended recipients cannot decipher or understand the contents of a message.
* **Integrity** - Assurance that transmitted data was not altered during transit.
* **Authentication** - Validates the source or origin of the sender.
* **Non-repudiation** - Undeniable proof of the legitimacy and authenticity of a message.

[*Learn more about authenticity vs. non-repudiation here.*](https://www.upguard.com/blog/authenticity-vs-non-repudiation)

Without cryptography, sending messages without threat actors stealing the information would be impossible. In theory, the strongest cryptographic schemes are impossible to break, even with the most powerful computers in the world with unlimited computing power.

eBook

A Complete Guide to Data Breaches

Free resource

### A Complete Guide to Data Breaches

Learn how to avoid a costly data breach with a comprehensive prevention strategy.

[Download now](/resources/complete-guide-to-data-breaches)

## Related posts

Learn more about the latest issues in cybersecurity.

Cybersecurity

#### [12 Cybersecurity Horror Stories of 2026 (No Costume Required)](/blog/cybersecurity-horror-stories-2026)

A warning ignored once becomes a headline. Read more about these 12 real 2026 cybersecurity incidents, and the sign each one gave before it made the news.

[](/team/revashni-moodley)

[Revashni Moodley](#)

October 14, 2026

Cybersecurity

#### [Left Unsupervised: 10 Times Access Outlived Its Authorization](/blog/10-times-access-outlived-authorization)

Access granted once shouldn’t mean access forever. Read more on how unmonitored access caused 10 of these real-life breaches and what they taught us.

[](/team/revashni-moodley)

[Revashni Moodley](#)

August 25, 2026

Cybersecurity

#### [Surviving a LockBit Ransomware Attack: The ROI of Visibility](/blog/surviving-a-lockbit-ransomware-attack)

Read how veteran CISO Nick Gicinto saved his alma mater from a LockBit ransomware attack by discarding the standard playbook.

[](/team/nicholas-sollitto)

[Nicholas Sollitto](#)

June 1, 2026

Cybersecurity

#### [Top 10 Security Events of 2025](/blog/top-security-events-of-2025)

Recap the ten most impactful events that reshaped the cybersecurity industry this year and the critical lessons each had to teach us. Read more here.

[](/team/revashni-moodley)

[Revashni Moodley](#)

October 14, 2026

Cybersecurity

#### [Risk Automations: The Shift From Catch-Up to Command](/blog/risk-automations-shift-catch-up-to-command)

Connect intelligence to system execution with Risk Automations, your new resolution layer for risk. Reduce remediation from hours to seconds - read more.

[](/team/revashni-moodley)

[Revashni Moodley](#)

December 1, 2025

Cybersecurity

#### [Shai-Hulud's True Lesson for CISOs: A Crisis of Communication](/blog/shai-hulud-lesson-for-cisos)

Shai-Hulud was driven by a communication crisis between security and engineering. Get a CISO's perspective on how to finally bridge this gap.

[](/team/phil-ross)

[Phil Ross](#)

September 3, 2026

[All posts](/blog)

Experience superior visibility and a simpler approach to cyber risk management

[Get a demo](/contact-sales)

[Free trial](/demo)
