What is encryption?
Encryption scrambles data with a key so only someone with the right key can read it again.
Drafted with AI from official documentation. Scripts were run in a test environment and repository links verified. Awaiting a human check. Did it work for you? Last edited Outdated?
Encryption transforms readable data into gibberish using a key, and the matching key turns it back. A locked box is the picture: anyone can carry the box, but only the key holder can open it. Symmetric encryption uses one shared key (AES). Asymmetric encryption uses a pair: a public key anyone may use to lock, and a private key that alone can unlock (RSA, Ed25519).
TLS encrypts your web traffic, SSH encrypts your remote sessions, full disk encryption protects a stolen laptop, and messaging apps encrypt end to end. Asymmetric keys also create digital signatures that prove who sent something. The maths is solid; real world failures come from lost keys, weak passwords and old algorithms, so keep software updated.
gpg -c secret.txt
openssl enc -aes-256-cbc -pbkdf2 -in notes.txt -out notes.encSee also: What is hashing? and What is TLS?
Did this work for you?
No votes yet. Be the first.
If it did not work, the report form below tells the editors what went wrong.
See also
- 0277 What is TLS? TLS is the encryption layer that puts the S in HTTPS, protecting data between your browser and a server. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0278 What is a certificate? A certificate is a digital ID card that proves a website or server is genuine, issued by a trusted authority. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0325 Fix: SSL certificate problem: unable to get local issuer certificate curl, git, pip or npm cannot chain the server's certificate to a root they trust. Usual causes: a corporate proxy that re-signs… Intermediate · Fixes an error · Linux, macOS, Windows Article Common errors · Making requests · TLS & certificates 15 Oct 2026
- 0355 TLS certificates explained What a certificate proves, who signs it, what the chain and expiry mean, and how to read any site's certificate from the… Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0356 Free HTTPS with Let’s Encrypt and certbot Install certbot, get a trusted certificate for your domain and let it configure nginx or Apache, or just obtain the files for… Beginner · Step by step · Linux Article TLS & certificates 15 Oct 2026
Repos in the wild
- certbot: the Let’s Encrypt client certbot/certbot The EFF's ACME client that obtains free TLS certificates from Let's Encrypt, can configure nginx and Apache for HTTPS automatically and renews everything on a timer. GitHub
- step-ca: run your own certificate authority for internal TLS and SSH smallstep/certificates step-ca from Smallstep is an open source certificate authority that issues TLS and SSH certificates for your own infrastructure, with ACME support so internal services get certificates the way public ones do. GitHub
History
Every saved edit is kept. The plot on the sleeve draws one line per edit. Open any edit to see exactly what changed.
- Dominik +852 chars