# Letterlocking

DevFeed: [Letterlocking](<https://devfeed.tech/articles/letterlocking-36869.md>)

Original publisher: [Read original article](<https://shostack.org/blog/letterlocking/>)

Author: Adam

Published: 2022-01-12T00:00:00Z

Content type: article

Language: en

Sources: [Shostack & Friends Blog](<https://devfeed.tech/sources/shostack-friends-blog.md>)

Topics: [Security](<https://devfeed.tech/topics/security.md>), [Cryptography](<https://devfeed.tech/topics/cryptography.md>)

Tags: [article](<https://devfeed.tech/tags/article.md>), [electronic](<https://devfeed.tech/tags/electronic.md>), [history](<https://devfeed.tech/tags/history.md>), [security](<https://devfeed.tech/tags/security.md>)

## AI overview

The article discusses letterlocking, a historical method of folding letters into their own envelopes to protect them from surreptitious readers. It describes how these techniques evolved, used paper manipulation and wax seals, and provided varying levels of security before mass-produced gummed envelopes and widespread cryptography.

## Source excerpt

Letterlocking is a lost art of protecting letters from surriptitious readers.