Sass

A stylesheet language that compiles to CSS and allows developers to use variables, nested rules, mixins, and functions.

A backward-compatible CSS language extension inspired by Sass that supports variables, mixins, operations, and functions.

Markdown

A lightweight markup language used to add formatting to plain text documents using simple, human-readable syntax.

Trace Context

Defines standard HTTP headers and a value format for propagating context information that enables distributed tracing.

RDF

A W3C standard model for describing and exchanging graph-based data on the web.

JSON Web Token

An open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object.

RelMeAuth

A proposed open standard for using rel-me links to profiles on OAuth supporting services to authenticate via either those profiles or your own site.

LLMs.txt

A proposed standard that provides structured content and instructions to guide large language models in understanding and summarizing a website's content.

CGI

An interface specification that enables web servers to execute an external program to process HTTP requests.

WebAssembly

A portable binary instruction format that runs in modern web browsers with near-native performance, enabling frontend coding in languages that were not traditionally used for web interfaces, such as C/C++, C#, and Rust.

Webmention

A simple protocol to notify any URL when a website links to it, and for web pages to request notifications when somebody links to them.

OpenAPI

A specification language for defining HTTP APIs, typically written in YAML or JSON.

Prerender

A deprecated browser hint that instructed web browsers to preload and render a web page in the background before navigation occurred.

ESI

A simple markup language used to define web page components for dynamic assembly and delivery of web applications at the edge of the Internet.

Humans.txt

A plain text file that allows website creators to identify and credit the people involved in developing a website.

Onion

Sites are websites on the dark web that use the .onion top-level domain and are only accessible through online routing through Tor.

OpenTelemetry

An open-source, vendor-neutral observability framework and toolkit for collecting, processing, and exporting telemetry data such as traces, metrics, and logs.

Rack

A minimal, modular interface and invocation convention that operates between Ruby web servers and web applications to standardize how HTTP requests and responses are exchanged.

ActivityPub

A decentralized social networking protocol used by various Fediverse services such as Mastodon, Pixelfed, and PeerTube.

XSLT

A language designed for transforming XML documents into other documents.