- Ada
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- IDE and editors
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- Language Agnostic
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- Introduction to Ada - Adacore
- Android Tutorial - tutlane
- Javatpoint Android Tutorial - javaTpoint
- Help messages will explain everything - explainshell
- Learn Shell Programming - learnshell
- C Tutorial - Scaler Topics
- Learn C - Learn-C
- C# Tutorial - tutlane
- C# Tutorial - W3Schools
- Codeasy - codeasy
- Learn C# - learnCS
- Learn C# - Codecademy
- C++ Programming Language - GeeksforGeeks
- C++ Tutorial - W3Schools
- C++ Tutorial - Scaler Topics
- CppKoans
- 4Clojure - Koans
- Clojure Koans - Clojure Koans
- ClojureScript Koans
- Try Clojure
- AWS API Gateway - registration required
- AWS Identity and Access Management (IAM) - registration required
- AWS Lambda - registration required
- AWS Simple Storage Service (S3) - registration required
- Google Cloud Platform
- Dart Official Codelabs - Dart
- Data Science Foundations - IBM SkillBuild (email address required)
- Essential Linear Algebra for Data Science and Machine Learning - KDnuggets
- Top 10 Data Science Projects for Beginners - KDnuggets
- git-game
- git-game-v2
- Git Tutorial - W3Schools
- Githug (Tutorial in shell)
- Learn Git Branching
- Learn git concepts, not commands - Nico Riedmann, Dev.to
- Learn Git with Bitbucket Cloud
- Try Git
- Visualizing Git Concepts with D3 - Wei Wang
- Go Koans
- Go Tutorial - W3Schools
- Learn Go - Google, Robert Griesemer, Rob Pike, and Ken Thompson (Codecademy) (account required)
- Start using Go - Microsoft
- The Go Tutorial
- CSS Diner
- CSS Speedrun | Test your CSS Skills - Vincent Will (HTML)
- CSS Tutorial - W3Schools
- Flex Box Adventure - Nick Bull
- Flexbox Defense
- Flexbox Froggy
- Grid Attack - Nick Bull
- Grid Garden
- HTML Tutorial - W3Schools
- HTML Tutorial - Scaler Topics
- Knights of the Flexbox Table
- Learn by doing beginner projects
- Learn CSS: an evergreen CSS course and reference to level up your styling expertise - Andy Bell, Rachel Andrew, Una Kravets, Adam Argyle, Rob Dodson, Jiwoong Lee, et al. (web.dev)
- Learn HTML & CSS interactively
- Prototyping a professional website
- Responsive Web Design Certification - freeCodeCamp
- Interactive Vim Tutorial - Henrik Huttunen
- Bootstrap 5 Tutorial - W3Schools
- Bootstrap Tutorial - tutlane
- Front End Development Libraries Certification: Bootstrap - freeCodeCamp
- CodingBat code practice
- Java at Codecademy
- Java Tutorial - W3Schools
- Java Tutorial - Scaler Topics
- Learn Java
- Learneroo Java tutorial
- ABC of JavaScript : An Interactive JavaScript Tutorial
- Codecademy jquery track
- Functional Programming in Javascript
- JavaScript Algorithms and Data Structures Certification - freeCodeCamp
- JavaScript in 14 minutes - Jeremy Thomas
- JavaScript interactive tutorial on CodeCademy
- JavaScript interactive tutorial on CoderMania
- JavaScript Tutorial - W3Schools
- JavaScript Tutorial - Scaler Topics
- Javascripting
- Learn JavaScript
- Learn knockout.js
- Learn to Code for Free – Grasshopper
- Learning Advanced JavaScript
- Try jQuery
- AngularJS - Step by Logical Step - Nicholas Johnson
- AngularJS Basics - Chris Smith
- AngularJS Tutorial - tutlane
- AngularJS Tutorial - W3Schools
- egghead.io: Learn AngularJS with Tutorial Videos & Training
- Learn AngularJS with free interactive lessons
- Front End Development Libraries Certification: jQuery - freeCodeCamp
- jQuery Tutorial - W3Schools
- Front End Development Libraries Certification: React - freeCodeCamp
- React Tutorial
- React Tutorial - W3Schools
- Front End Development Libraries: Redux - freeCodeCamp
- Kotlin tutorial
- Kotlin Tutorial - W3Schools
- Learn Kotlin - Galina Podstrechnaya, Alex DiStasi (Codecademy) (account required)
- Unit 1: Kotlin Basics Android (account required)
- CodeCombat - Python, JavaScript, CoffeeScript, Clojure, Lua, Io
- Codility
- Introduction to the Coding Interview Prep Algorithms (freeCodeCamp)
- Python Tutor - Python, Java, JavaScript, TypeScript, Ruby, C, C++
- The Fullstack Tutorial for GraphQL
- Learning operating system development using Linux kernel and Raspberry Pi - Sergey Matyukevich (:construction: in process)
- Operating System Tutorial - Scaler Topics
- Project eXpOS: eXperimental Operating System - Dr. Murali Krishnan K., Department of Computer Science and Engineering of the Calicut National Institute of Technology (HTML)
- Node School
- Node.js Tutorial - tutlane
- Node.js Tutorial - W3Schools
- MongoDB Koans
- MongoDB Tutorial - W3Schools
- Try Redis
- CodeCademy PHP
- Learn PHP
- PHP tutorial - W3Schools
- Codecademy Python course
- Computer Science Circles - Centre for Education in Mathematics and Computing (University of Waterloo)
- Data Analysis with Python Certification - freeCodeCamp
- futurecoder - Alex Hall
- How to Think Like a Computer Scientist: Learning with Python, Interactive Edition
- Learn Python
- Learn Python Step by Step
- Python for Everybody - Interactive - Barbara Ericson
- Python Koans
- Python Pandas Tutorial: A Complete Introduction for Beginners - George McIntire, Brendan Martin, Lauren Washington
- Python Programming Language - GeeksforGeeks
- Python Tutorial - tutlane
- Python Tutorial - W3Schools
- Python Tutorial - Scaler Topics
- Scientific Computing with Python Certification - freeCodeCamp
- Learn R - Codecademy (account required)
- R Tutorial - W3Schools
- Regex Crossword - Ole Michelsen, Maria Hagsten Michelsen
- RegExp Playground - Lea Verou
- CryptoZombies.io - Loom Network
- Intro to SQL: Querying and managing data - Khan Academy
- SQL at Codecademy
- SQL Server Tutorial - tutlane
- SQL Teaching
- SQL Tutorial - W3Schools
- SQL Tutorial - Scaler Topics
- SQLBolt
- XML Tutorial - W3Schools