# The Useful Layer

> The Useful Layer is an independent publication about everyday internet systems and defensive account security. It gives readers the mechanism, vocabulary, and limits behind familiar technology, with official sources close at hand.

The Useful Layer publishes original, long-form guides about Technology, one understandable layer at a time.. Every article opens with a concise direct answer, is structured with clear headings and FAQs, and reflects mainstream expert consensus.

## Internet Basics

- [How DNS Works: From Domain Name to IP Address](https://nstec.com/how-dns-works/): The Domain Name System, or DNS, is a distributed naming system that helps a device find information associated with a domain name, including an IP address.

## Security Hygiene

- [What Is Multifactor Authentication? MFA Explained](https://nstec.com/what-is-multifactor-authentication/): Multifactor authentication, or MFA, requires more than one distinct type of authentication factor.

## Full text for LLMs

- [llms-full.txt](https://nstec.com/llms-full.txt): every article as plain markdown in one file
- Each article is also available as markdown at https://nstec.com/<slug>.md

## Site

- [About](https://nstec.com/about/): editorial approach and standards
- [All articles](https://nstec.com/all/)
- [Contact](https://nstec.com/contact/)