A generation ago, an ordinary person’s only brush with cryptography might be watching a spy movie. Now we all rely cryptography every day, whether we realize it or not.
Before you could read this web page, your web browser and my web server exchanged public keys, using asymmetric encryption to exchange keys for symmetric encryption. The modern web, and even the modern economy, would not be possible without encryption.
Here are some of the blog posts on this site related to cryptography.