Encryption sits at the core of nearly every digital system you use, from secure websites and messaging apps to the password vault on your phone. It’s the mechanism that turns readable information into protected data, and then back again when authorized systems need it. Let's take a moment and look at what encryption actually is, how plaintext becomes ciphertext, why keys matter, and where modern encryption shows up in everyday technology — along with the reasons it has become a baseline requirement for privacy, security, and compliance.
Contents:
What is encryption?
Encryption is the process of converting readable data into an unreadable, coded format to prevent unauthorized access. During encryption, an algorithm and a secret key turn your information into a scrambled form called ciphertext. Only someone with the matching decryption key can convert it back into its original, readable state (plaintext).
Modern data encryption protects sensitive data in two main situations:
Data at rest. Files on storage devices, database records, backups, and password vaults are stored as encrypted data, so a stolen laptop or copied server snapshot does not expose everything inside.
Data in transit. When you visit a website over HTTPS, send an encrypted message, or connect through virtual private networks, network encryption prevents outsiders from reading what travels between your device and the service.
Because encryption and decryption are two sides of the same process, you will often see the term “encryption method” used to describe the full journey.
Plaintext, ciphertext, and keys
A typical encryption flow looks like this:
You start with plaintext — a password, a document, or customer payment card data.
An encryption algorithm (for example, the advanced encryption standard or a modern encryption technique like XChaCha20) combines that plaintext with a cryptographic key.
The result is ciphertext — encrypted data that looks random.
Later, a matching decryption key runs the data through the reverse process to decrypt the data and restore the original information.
The same idea works whether you are protecting a single encrypted message, full-disk database encryption, or encryption systems inside cloud storage providers.
What happens to your data when it is encrypted?
When your data is encrypted:
The actual bits on the disk or in transit become ciphertext.
Applications that have the right encryption keys decrypt data on the fly when you need it.
If an attacker copies the files or sniffs the traffic, they only get encrypted data — not passwords, card numbers, or readable emails.
That is why most modern encryption methods are built into everything from secure sockets layer (SSL) and transport layer security (TLS) on the web to smartphone full-disk encryption and password managers.
Why is encryption important?
Even for advanced users, it can be easy to underestimate how much of your daily life runs on hidden cryptography. Encryption underpins four big areas: privacy, security, data integrity, and compliance.
Privacy
Without encryption, anyone (provided they have the right skill set) on the path between your device and a service could read your traffic. When websites use TLS instead of legacy SSL, and when apps encrypt data before sending it, outsiders (including bad actors and cyber crooks) see only encrypted data, not the details of your messages, searches, or logins.
On your devices, full-disk and database encryption protect sensitive data such as notes, photos, and password vault entries. If someone steals your phone or laptop, a strong screen lock and device encryption can stop them from browsing through your life.
Security
Most serious breaches involve sensitive data — password hashes, access tokens, personal records, or payment card data. Strong data encryption and careful key encryption reduce the the risk factors when something goes wrong:
A copied server image still holds encrypted data instead of live records.
Intercepted traffic from network encryption is useless without keys.
Brute force attacks against well-chosen encryption algorithms and long keys become impractical.
Attackers may still try brute force attacks against weak passwords or older ciphers, but when organizations and individuals pick modern encryption techniques and handle key management properly, they make those attacks far more expensive than the stolen data is worth.
Data integrity
Encryption by itself hides content. Combined with authentication codes and modern encryption methods like authenticated encryption, it can also help you to:
Detect if someone modified encrypted data in transit.
Ensure that both the sender and the recipient are seeing the same message.
Maintain data integrity for backups and database encryption.
Protocols like TLS use both encryption and message authentication so that the browser can tell if the ciphertext has been altered before it decrypts the data.
Compliance
Most industries now treat strong encryption as a basic requirement for data security:
Payment rules require organizations to encrypt customer payment card data, especially at rest.
Healthcare and financial regulations expect encryption of sensitive data in databases, backups, and logs.
Many standards from the National Institute of Standards and Technology (NIST) point to modern ciphers like the advanced encryption standard instead of older options like the data encryption standard and triple data encryption standard.
For companies, that means encryption key management and broader key management practices are not optional extras — they are part of staying compliant and avoiding fines.
Is encryption good or bad?
Encryption can be abused, but the technology itself is simply a tool. Cybercriminals may hide their own traffic using the same encryption software that protects you. Still, for everyday users and organizations, encryption is overwhelmingly a force for good: it helps protect sensitive data, supports secure data handling, and gives people a realistic way to control who can see what.
What is an encryption key?
An encryption key is a cryptographic key — a long, random string of bits generated by software or hardware — that controls the encryption and decryption process. When you see references to 128-bit or 256-bit keys, that number describes the key’s length in bits.
A few important points:
Longer keys make brute force attacks far harder because there are vastly more possible combinations.
Encryption keys must be generated with high-quality randomness so that attackers cannot guess or reproduce them.
In modern encryption systems, keys are rarely typed by humans — they are created and stored by software.
Types of modern encryption
There are many types of encryption, but most modern encryption techniques fall into two broad groups: symmetric encryption and asymmetric encryption. Many encryption systems combine both.
Symmetric encryption (or private key encryption)
Symmetric encryption uses the same key to perform both encryption and decryption. That key is often called a secret key or private key in this context.
Key characteristics:
Speed. Symmetric encryption algorithms are fast and efficient, which makes them ideal for large files, streaming video, or full-disk encryption.
Shared secret. Both the sender and the receiver must know the same private key in advance, which is why you will also see the phrase “symmetric key encryption.”
Common encryption algorithms. Examples include the advanced encryption standard (AES), the older data encryption standard and triple data encryption standard, and newer stream ciphers like ChaCha20 and XChaCha20.
Block ciphers like AES are classic symmetric block cipher designs and are often referred to as a symmetric key block cipher family. In contrast, stream ciphers like ChaCha20 encrypt data one piece at a time rather than in fixed blocks.
When people talk about a secure AES algorithm or a more secure AES algorithm, they usually mean using AES with longer keys and modern modes of operation.
Asymmetric encryption (or public key encryption)
Asymmetric encryption — also called public key encryption or public key cryptography — uses separate keys:
A public key that anyone can have.
A matching private key that only the owner should know.
Whatever one key encrypts, only the other key can decrypt. That property enables several powerful patterns:
You can publish your public key so that anyone can send you an encrypted message.
You keep the private key safe so you alone can decrypt data.
Because the public key cannot be used to decrypt data, it is safer to share.
Common public key algorithms include RSA, elliptic-curve cryptography (ECC), and Diffie-Hellman-based key exchange schemes.
In practice, public key cryptography is slower than symmetric encryption algorithms, so systems rarely use it to encrypt bulk data. Instead, public key encryption is used to:
Exchange symmetric keys securely over an untrusted network.
Verify digital signatures.
Establish trust in protocols like TLS.
Hybrid encryption in modern protocols
Most types of encryption you encounter online are actually hybrid encryption:
A client and server use asymmetric encryption to authenticate and agree on shared symmetric keys.
Once the handshake is complete, they switch to fast symmetric encryption for the rest of the session.
Protocols like transport layer security then use those keys for both encryption and decryption of the data they exchange.
This pattern combines the strengths of both approaches: flexible key exchange with robust security and high-performance symmetric ciphers.
Which type of encryption is safer?
Instead of asking which type of encryption is “the safest,” it is better to ask which encryption method is right for a given job.
For large volumes of data — backups, long video streams, database encryption — symmetric encryption is the practical choice. Symmetric key encryption with AES or XChaCha20 is fast and, when implemented correctly, offers robust security.
For identity, key exchange, and signatures, asymmetric encryption and public key cryptography are essential. They let strangers on the internet establish secure channels without meeting in person first.
In real-world encryption systems, you rarely have to choose between symmetric encryption and asymmetric encryption. Most modern encryption methods use:
Asymmetric cryptography to establish trust and exchange keys.
Symmetric ciphers to protect data for the rest of the session.
Additional mechanisms to ensure data integrity and safe key management.
For advanced users, the safer choice is almost always to rely on well reviewed, widely deployed encryption algorithms — such as the advanced encryption standard or modern stream ciphers — rather than inventing something new.
How can NordPass encryption help you stay safe online?
Passwords, passkeys, and payment card details are some of the most sensitive data you own. If someone gets into the accounts those secrets protect, they can reset logins, drain funds, or impersonate you. A password manager gives you a reliable and simple way to protect sensitive data without memorizing everything.
NordPass is built around modern encryption techniques, so your vault stays safe even if someone copies the encrypted data from a device or server.
XChaCha20: Modern encryption for your password vault
NordPass uses the XChaCha20 algorithm to encrypt your password vault. XChaCha20 is a symmetric key algorithm:
It uses a single symmetric key to scramble and unscramble data, just like AES.
It is a 256-bit stream cipher rather than a block cipher, encrypting each piece of data in a continuous stream.
It extends the nonce (a value that must never repeat with the same key) to reduce the risk of mistakes that can weaken network encryption.
Practically, this means your vault items — logins, secure notes, customer payment card data, and other secrets — are stored as encrypted data using a modern encryption method designed for speed and security. Furthermore, your master password is never stored as an encryption key. Instead, it helps derive a cryptographic key that unlocks your vault locally. In turn that means that if someone steals the vault file, they still have to break strong encryption and use brute force attacks against keys and passwords.
Give NordPass a try
If you want to protect sensitive data like your logins, personal notes, and payment details with cutting-edge encryption, a password manager is one of the easiest upgrades you can make.
The NordPass password manager offers features like secure item sharing along with additional tools that help you spot weak or reused passwords before attackers do. Combined with modern encryption methods such as XChaCha20, it gives you a realistic, everyday way to keep your digital life locked down — without living in spreadsheets or trying to remember dozens of complex passwords.