Tech Skills Glossary for Recruiters

Created: 2001 (the Agile Manifesto).

Agile is a way of running software projects in short iterations with frequent feedback, instead of one long plan delivered at the end. It is a working method, not a technology.

Created: no single date; the term spread with large language model tools in the mid-2020s.

An AI agent is a program built on a large language model that can plan steps and take actions (call tools, edit code, browse, send requests) rather than only answer questions.

Created: 2015.

Airflow is an open-source tool for scheduling and monitoring data pipelines (workflows that move and transform data on a schedule). It was created at Airbnb and is written in Python.

Created: 2008 (first Android phone).

Android is Google's mobile operating system and the most widely used one in the world.

Created: 2016. Its predecessor AngularJS: 2010.

Angular is a frontend framework from Google for building web applications, written in TypeScript. It is a complete rewrite of the older AngularJS, and the two are not compatible.

Created: 2012.

Ansible is an open-source tool, now maintained by Red Hat, for automating server configuration and software deployment.

Created: 2006.

AWS is Amazon's cloud platform: rentable servers, databases, storage and hundreds of other services. It is the largest cloud provider.

Created: 2010 (commercially available; announced in 2008).

Azure is Microsoft's cloud platform and the main competitor of AWS.

A role, not a technology.

Backend (server-side) development means building the parts of an application that run on servers: business logic, databases, APIs and integrations. Users do not see it directly.

Created: 1989.

Bash is the standard command-line shell on Linux and macOS, used to write small automation scripts.

Created: 2011.

Bootstrap is a CSS framework (a library of ready-made styles and components) for building websites quickly.

Created: 2021 (first release); version 1.0 in 2023.

Bun is a fast JavaScript runtime, an alternative to Node.js and Deno.

Created: 1972.

C is one of the oldest programming languages still widely used. Operating systems, device drivers and embedded devices are written in it.

Created: 2000.

C# (pronounced "C sharp") is Microsoft's main programming language, used with .NET for backend systems, desktop apps and games (Unity).

Created: 1985.

C++ is a fast, powerful and complex programming language, an extension of C.

Created: November 2022.

ChatGPT is OpenAI's AI chatbot, built on large language models.

A practice, not a single tool.

CI/CD means automatically testing and deploying code every time it changes, instead of releasing manually.

Created: 2023 (first model, March 2023; first public model, Claude 2, July 2023).

Claude is the family of AI models and the AI assistant made by Anthropic, a competitor of ChatGPT.

Created: February 2025 (research preview); generally available in May 2025.

Claude Code is Anthropic's AI coding tool. It works in the terminal and in code editors, reads a codebase and writes, edits and tests code on the developer's behalf.

Created: 1959.

COBOL is one of the oldest programming languages. It still runs core systems in banks, insurance companies and governments.

Created: 1996.

CSS is the language that defines how web pages look: layout, colours, fonts and responsiveness on mobile.

Created: 2023.

Cursor is an AI-powered code editor built on Visual Studio Code.

Created: 2017.

Cypress is a tool for automated end-to-end testing of web applications (a program clicks through the app like a user would).

Created: 2011.

Dart is a programming language from Google, used mainly with Flutter.

Created: 2013 (company founded by the creators of Apache Spark).

Databricks is a cloud platform for data engineering, analytics and machine learning, built around Apache Spark.

Created: 2016; version 1.0 in 2021.

dbt is a tool for transforming data inside a data warehouse using SQL, with testing and documentation built in.

Created: 2018; version 1.0 in 2020.

Deno is a JavaScript and TypeScript runtime by the original creator of Node.js, designed as a more secure, modern alternative.

Created: 2009 (the term spread with the first DevOpsDays conference).

DevOps is a culture and a set of practices that join software development and IT operations: automation, CI/CD, infrastructure as code and monitoring.

Created: 2005.

Django is the most popular full-featured Python framework for building web applications and backends.

Created: 2013.

Docker packages an application with everything it needs into a "container" that runs the same way on any machine.

Created: 2010.

Elasticsearch is a search and analytics engine used for site search, log analysis and monitoring.

Created: 2013.

Electron lets developers build desktop applications (Windows, macOS, Linux) with web technologies: HTML, CSS and JavaScript. Visual Studio Code and Slack's desktop app are built with it.

Created: 2012.

Elixir is a programming language for highly reliable, concurrent systems (chat, messaging, real-time apps). Its main web framework is Phoenix.

Created: 2010.

Express is the classic minimal web framework for Node.js.

Created: 2018.

FastAPI is a modern Python framework for building APIs. It is popular in AI and machine-learning products.

Created: 2016 (public release; invite-only preview from December 2015).

Figma is a browser-based design tool for user interfaces, used by designers and developers together.

Created: 2010.

Flask is a lightweight Python web framework.

Created: 2017 (first public version); stable 1.0 in December 2018.

Flutter is Google's framework for building apps for iOS, Android, web and desktop from a single codebase. It uses the Dart language.

A role, not a technology.

Frontend (client-side) development means building what users see and interact with in a browser, using HTML, CSS and JavaScript or TypeScript, usually with a framework such as React, Angular or Vue.js.

A role, not a technology.

A full-stack developer works on both the frontend and the backend of an application.

Created: 2005.

Git is the standard version control system: it tracks every change to code and lets teams work on the same codebase.

Created: 2008. GitHub Actions (its CI/CD tool): 2019.

GitHub is the most popular platform for hosting Git repositories, code review and collaboration. Owned by Microsoft.

Created: June 2021 (technical preview); generally available in June 2022.

GitHub Copilot is an AI coding assistant that suggests and writes code inside the code editor.

Created: 2011.

GitLab is a platform for Git repositories with built-in CI/CD, an alternative to GitHub. It is popular in companies that host their own tools.

Created: 2009 (first public release); version 1.0 in 2012.

Go is a simple, fast programming language from Google, popular for backend services, cloud tools and infrastructure. Docker and Kubernetes are written in Go.

Created: 2008 (App Engine, its first service).

Google Cloud is Google's cloud platform, the third-largest after AWS and Azure. It is known for data and AI services such as BigQuery.

Created: 2014.

Grafana is a tool for building dashboards that show metrics and logs from systems.

Created: 2015 (public release by Facebook).

GraphQL is a way for apps to request exactly the data they need from a server, an alternative to REST APIs.

Created: 2006.

Hadoop is a framework for storing and processing very large data sets across many machines.

Created: 1993 (first formal draft; first described in 1991).

HTML is the markup language that defines the structure of every web page.

Created: 2007 (first iPhone); third-party apps from 2008.

iOS is Apple's operating system for iPhone.

Created: 1995.

Java is one of the most popular programming languages, used for large backend systems (especially in banking, insurance and enterprise), Android apps and much more.

Created: 1995.

JavaScript is the programming language of the web browser. It also runs on servers via Node.js.

Created: 2011 (as a fork of the older Hudson).

Jenkins is an open-source automation server used for CI/CD.

Created: 2014.

Jest is a popular framework for writing automated tests for JavaScript and TypeScript code, created by Facebook.

Created: 2021 (stable 1.0; previews from 2019).

Jetpack Compose is Google's modern toolkit for building Android user interfaces in Kotlin.

Created: 2002.

Jira is Atlassian's tool for tracking tasks, bugs and sprints.

Created: 2006.

jQuery is a JavaScript library that made working with web pages easier.

Created: 2011.

Kafka is a platform for streaming large volumes of events and messages between systems in real time. It was created at LinkedIn.

Created: 2011 (unveiled); version 1.0 in 2016. Google's preferred language for Android since 2019.

Kotlin is a modern programming language from JetBrains, the main language of Android development and increasingly used on backends.

Created: 2014.

Kubernetes is a system for running and managing many containers (e.g. Docker containers) across clusters of servers. It came from Google.

Created: October 2022.

LangChain is an open-source framework for building applications on top of large language models (chatbots, AI agents, RAG systems).

Created: 2011.

Laravel is the most popular PHP web framework.

Created: 1991.

Linux is the open-source operating system that runs most servers, the cloud and Android phones.

Created: the underlying "transformer" design dates from 2017; GPT-3 (2020) and ChatGPT (2022) made LLMs mainstream.

An LLM is an AI model trained on huge amounts of text that can write, summarise, translate and code. ChatGPT and Claude are built on LLMs.

A field with decades of history; the popular modern tools date from 2007–2016.

Machine learning teaches computers to find patterns in data and make predictions without being explicitly programmed for each case.

Created: November 2024.

MCP is an open standard, introduced by Anthropic, that lets AI assistants and agents connect to external tools and data sources in a uniform way.

An architecture style, popularised in the early 2010s.

Microservices means building an application as many small independent services instead of one large program (a "monolith").

Created: 2009.

MongoDB is the most popular NoSQL database. It stores data as flexible documents instead of tables.

Created: 1995.

MySQL is a widely used open-source relational (SQL) database, owned by Oracle. MariaDB is a fork of it.

Created: 2017.

NestJS is a structured backend framework for Node.js, written in TypeScript and inspired by Angular.

Created: 2016.

Next.js is a framework built on React for creating fast websites and full-stack web applications.

Created: 2009.

Node.js lets JavaScript run on servers, so the same language can be used on the frontend and the backend.

A category of databases; the term spread in the late 2000s.

NoSQL databases store data in ways other than SQL tables: documents, key-value pairs, graphs or wide columns. Examples: MongoDB, Redis, Cassandra, DynamoDB.

Created: 2016.

Nuxt is a framework built on Vue.js, the Vue counterpart of Next.js.

Created: 2002 (.NET Framework, Windows only); 2016 (.NET Core, cross-platform, today just ".NET").

.NET is Microsoft's development platform for building backends, web apps (ASP.NET), desktop apps and more, mainly with C#.

Created: 2008.

pandas is the standard Python library for working with tabular data (like spreadsheets in code).

Created: 1995.

PHP is a server-side language that powers a large part of the web, including WordPress.

Created: 2020.

Playwright is Microsoft's tool for automated end-to-end testing of web applications across browsers.

Created: 1996 under this name (the Postgres project dates from the 1980s).

PostgreSQL is a powerful open-source relational (SQL) database and one of the most popular databases among developers.

Created: 2015 (general release; an early version appeared in 2011 as "Project Crescent").

Power BI is Microsoft's business intelligence tool for building reports and dashboards.

Created: 2012.

Prometheus is an open-source system for collecting and alerting on metrics from servers and applications.

A skill that emerged with LLMs in the early 2020s.

Prompt engineering is writing instructions and context for AI models so they produce reliable, useful results.

Created: 1991.

Python is a popular, easy-to-read programming language used for backend development, data analysis, machine learning, AI, automation and scripting.

Created: 2016.

PyTorch is the leading library for building and training deep learning models. It came from Meta (Facebook).

Created: 2020 (the term comes from a 2020 research paper).

RAG is a technique where an AI model first looks up relevant documents (e.g. a company knowledge base) and then answers using them, which makes answers more accurate and up to date.

Created: 2013.

React is the most popular JavaScript library for building user interfaces, created by Facebook (Meta).

Created: 2015.

React Native is a framework for building iOS and Android apps with JavaScript or TypeScript and React.

Created: 2009.

Redis is an extremely fast in-memory database used for caching, sessions and queues.

Created: 2015.

Redux is a library for managing application state (data), mostly used with React.

Created: 2000 (described in Roy Fielding's dissertation).

REST is the most common style of designing web APIs, the interfaces through which apps and servers exchange data.

Created: 1995.

Ruby is a programming language designed for developer productivity and readability, used mainly with the Ruby on Rails framework.

Created: 2004.

Ruby on Rails is a full-stack web framework for Ruby that favours conventions and fast development.

Created: 2012 (first public release); version 1.0 in 2015.

Rust is a modern systems programming language that is as fast as C and C++ but prevents many common bugs and security issues.

Created: 1999.

Salesforce is the leading CRM (customer relationship management) platform. It has its own programming language, Apex.

Created: 2004.

Scala is a programming language that runs on the Java platform and combines object-oriented and functional programming. Apache Spark is written in Scala.

Created: 2007 (project start); first public release in 2010.

scikit-learn is the standard Python library for classical machine learning (classification, regression, clustering).

Created: 1995.

Scrum is the most common agile framework: work in fixed sprints (usually two weeks) with defined roles (Scrum Master, Product Owner, Development Team).

Created: 2004.

Selenium is the long-established tool for automating web browsers, mostly for testing.

Created: 2015 (product launch; the company was founded in 2012).

Snowflake is a cloud data warehouse for storing and analysing large amounts of company data with SQL.

Created: 2014.

Solidity is the main programming language for smart contracts on the Ethereum blockchain.

Created: 2014 (version 1.0; earlier versions from 2012).

Spark is an engine for processing very large data sets quickly across many machines.

Created: 2002 (Spring Framework; 1.0 in 2004). Spring Boot: 2014.

Spring is the dominant framework for Java backend development. Spring Boot is the modern, simplified way of using it.

Created: the early 1970s (first described in 1974).

SQL is the language for querying and managing data in relational databases (MySQL, PostgreSQL, SQL Server, Oracle and others).

Created: 2016.

Svelte is a frontend framework that compiles components into very efficient JavaScript. SvelteKit is its full-stack framework.

Created: 2014.

Swift is Apple's programming language for iOS, macOS, watchOS and other Apple platforms. It is the successor to Objective-C.

Created: 2019.

SwiftUI is Apple's modern framework for building app interfaces in Swift.

Created: 2003.

Tableau is a data visualisation and business intelligence tool, now owned by Salesforce.

Created: 2019 (version 1.0).

Tailwind CSS is a popular CSS framework that styles pages using small utility classes directly in the HTML.

Created: 2015.

TensorFlow is Google's library for building and training machine learning models.

Created: 2014.

Terraform is a tool for defining cloud infrastructure (servers, networks, databases) as code, so it can be created and changed automatically.

Created: 2012.

TypeScript is JavaScript with types, developed by Microsoft. It makes large codebases safer and easier to maintain.

Created: 2005.

Unity is a popular game engine for mobile, PC, console and VR games, programmed in C#.

Created: 1998 (first game released with it).

Unreal Engine is Epic Games' high-end game engine, programmed in C++ and with visual scripting ("Blueprints").

Created: 2020.

Vite is a fast build tool for frontend projects, created by the author of Vue.js.

Created: 2014.

Vue.js is a popular frontend framework, an alternative to React and Angular.

Created: 2014.

Webpack is a tool that bundles frontend code for the browser.

Created: 2003.

WordPress is the most popular website platform (CMS), written in PHP.