encryption

basicwidespread

Encryption is a procedure that converts data into an unreadable string of characters, and only the person with the key can decrypt it.

In plain terms

Imagine putting your letter not in an envelope but in a sealed steel strongbox to which only the recipient has the key. The postman can carry it, the neighbor can shake it, but no one can see the contents. Encryption does the same with your data: the message or file becomes a meaningless string of characters that can only be made readable again with the correct key.

You use it countless times a day without noticing: when you use online banking, send a message, pay with a card, or unlock your phone. Encryption mainly protects in two situations: when data is in transit on the internet, and when it is stored on a device or server.

In the age of AI, this has become even more important because we are sharing more personal and corporate data with chatbots and AI agents. Encryption protects the data in transit and at rest, but it does not decide how the provider uses it on its own side. That is a matter of contract and regulation.

How it works

The sender's device takes the original, readable data (called plaintext) and mixes it using a mathematical procedure and a key.
The result is the encrypted text: anyone intercepting it without the key sees only a seemingly random sequence of characters.
In symmetric encryption, the same key locks and unlocks. This is fast, but the key must somehow be securely delivered to the other party.
In asymmetric (public-key) encryption, there is a key pair: anyone can lock the message with the public key, but only the secret pair can unlock it. This allows a secure connection to be established without a prior shared secret. The fact that the public key truly belongs to the other party is verified on the web by certificates.
In practice, the two are combined: your browser uses a public-key method to agree on a shared key with the website, after which traffic flows via fast symmetric encryption.

An everyday example

When the web address in your browser's address bar starts with "https://", the data travelling between you and the website is encrypted. If you enter your bank card number on such a page on a café's open Wi-Fi, an eavesdropper on the network sees only a meaningless string of characters instead of the content, and at most learns which site you are connecting to. However, "https" only protects the connection: it does not guarantee that the site itself is trustworthy, because fraudulent sites use it too.

Who is affected

everyoneYour messages, photos, password manager content, and phone data are protected by encryption from becoming readable if they fall into unauthorized hands.

bank customer, investorThe security of online banking, mobile banking, and card payments depends on your data being encrypted during transmission and storage. → Money

entrepreneur, executiveIf an encrypted laptop is lost or an encrypted database is stolen, and the key has not fallen into unauthorized hands, the damage and data protection liability are much smaller than with unprotected data.

developerYou must ensure that your application and the AI agent built on it handle keys and customer data encrypted, and user passwords hashed. → Code

A common misconception

MythIf a service is encrypted, then no one except me can see my data.

In realityEncryption only protects against those who do not have the key. If the key is with the provider, they can access the content. In end-to-end encryption, the key is only with you and the recipient, but the data is still readable on your and the recipient's device. Thus, a compromised phone or an unencrypted backup remains a risk.

Limits and risks

Encryption is only as good as the security of the key: a weak password, a stolen key, or a phishing scam can bypass even the strongest procedure.
The content is hidden, but the accompanying data is typically not: it may remain visible who you communicated with, when, and how much.
If you lose the key or the recovery code, you will no longer have access to your own data. Ransomware exploits this by encrypting your files.
What you enter into an AI service is encrypted en route, but on the provider's server it usually must be decrypted for processing. Therefore, check the terms of use for sensitive data.

Similar, but not the same

hashing – Hashing creates a one-way fingerprint of data from which the original cannot be reconstructed, whereas encryption is reversible with a key.
anonymization – Anonymization permanently removes personally identifiable parts from the data, while encryption preserves the entire data but locks it away.
coding – Encoding only rewrites the data into another format, without a key or secret, so anyone can reverse it – it offers no protection.

Related concepts

Broader

cryptography, data security, cybersecurity, data protection

Narrower

End-to-end encryption, symmetric encryption, public-key encryption, post-quantum encryption, homomorphic encryption

On the edge

hashing, digital signature, authentication, ransomware, VPN

A brief history

Cryptography has ancient origins: Julius Caesar already used a letter-shift method to protect his messages. The basic idea of public-key cryptography was published by Whitfield Diffie and Martin Hellman in 1976; the first practical public-key encryption method, RSA, was created in 1977. The most widely used symmetric standard today, AES, was adopted in 2001 by the US National Institute of Standards and Technology (NIST).

Where things stand

At the end of 2026, the vast majority of web traffic, messaging apps and phones are encrypted by default. The industry's main task is the transition to methods that also resist quantum computers, whose first standards NIST published in 2024.

Status: 2026 November

In the news

Appears in 3 Agent Age stories; the curve shows weekly occurrence in the news magazine.

School bomb threats aim to cause disruption; AI may make the threat worseOct 20, 2026 · Education & Family
UMG and Sony file new suit against Suno; Suno admits scraping YouTube audioOct 10, 2026 · Jog
WhatsApp to screen suspected scam messages with on-device AIAug 31, 2026 · Money

Also known as

encryption · encryption · encryption · encryption · encryption · data encryption · data encryption · encryption

Sources

This entry was machine-edited and has undergone machine expert review; the “In the news” section updates automatically from Agent Age stories.