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21 tutorials and 648 lessons. Every one starts from zero, with examples you can edit and run.
The language for building web pages
HTML is the standard markup language for creating web pages. Learn elements, attributes, text formatting, links, images, tables, lists, forms, media and semantic layout from scratch.
The language for styling web pages
CSS controls how HTML looks. Learn selectors, colours, the box model, typography, positioning, Flexbox, Grid, transitions, animations and responsive design.
The programming language of the web
JavaScript makes web pages interactive. Learn variables, data types, functions, objects, arrays, loops, the DOM, events, classes, modules, promises, async/await and the Fetch API.
JavaScript with types
TypeScript adds static types to JavaScript so you catch mistakes before your code runs. Learn types, arrays, tuples, objects, functions, unions, interfaces, classes, generics, utility types and more. Code compiles live in your browser.
The language for working with databases
SQL is the standard language for storing, reading and changing data in relational databases such as MySQL, PostgreSQL, SQL Server and SQLite. Practise every query live on a sample shop database.
The popular NoSQL document database
MongoDB stores data as flexible JSON-like documents instead of tables. Learn databases and collections, inserting, finding, query operators, projection, sorting, updating, deleting, indexes, the aggregation pipeline and using MongoDB from Node.js.
A popular, beginner-friendly language
Python is used for web development, automation, data science and AI. Learn syntax, data types, strings, lists, dictionaries, control flow, functions, classes, modules, files, exceptions and more.
Fast numerical computing in Python
NumPy is the foundation of data science in Python. Learn arrays, data types, indexing, slicing, shapes, reshaping, joining, searching, sorting, filtering, maths, statistics and random numbers. Runs live in your browser.
Data analysis with Python
Pandas is the most popular Python library for working with tables of data. Learn Series and DataFrames, reading CSV data, selecting, filtering, sorting, cleaning, grouping, merging and summarising data. Runs live in your browser.
A server-side scripting language for the web
PHP powers WordPress, Laravel and a large part of the web. Learn syntax, variables, strings, arrays, functions, forms, sessions, cookies, files, OOP, MySQL with PDO and JSON.
Write once, run anywhere
Java is used for Android apps, enterprise systems and backend services. Learn syntax, types, strings, control flow, arrays, methods, classes, inheritance, interfaces, collections, exceptions and more.
The foundation of modern programming
C is a fast, low-level language used for operating systems, embedded devices and performance-critical software. Learn syntax, types, operators, control flow, arrays, strings, pointers, functions, structs, memory and files.
High-performance programming with objects
C++ powers games, browsers, trading systems and embedded software. Learn syntax, I/O, types, strings, control flow, functions, references, pointers, classes, inheritance, templates, the STL and exceptions.
Modern, versatile language for .NET
C# is used for web APIs (ASP.NET Core), desktop apps, Unity games and cloud services. Learn syntax, types, strings, control flow, arrays, methods, classes, inheritance, interfaces, collections, LINQ, exceptions and async.
Build responsive sites fast
Bootstrap is the most popular CSS framework for responsive, mobile-first websites. Learn the grid, typography, colours, buttons, cards, navbars, forms, modals, alerts and utilities.
Utility-first CSS framework
Tailwind CSS lets you style pages directly in your HTML with small utility classes. Learn spacing, colours, typography, sizing, borders, Flexbox, Grid, responsive design, hover and focus states, dark mode and building components.
Write less, do more
jQuery is a fast JavaScript library that simplifies DOM manipulation, events, effects and AJAX. It is still used on millions of websites, including WordPress sites.
Build user interfaces with components
React is the most popular JavaScript library for building user interfaces. Learn JSX, components, props, state, events, lists, forms, hooks (useState, useEffect, useRef, useContext) and data fetching.
The progressive JavaScript framework
Vue.js is an approachable framework for building user interfaces. Learn the template syntax, reactivity, directives, events, forms, computed properties, watchers, components, props and emits, slots and lifecycle hooks.
JavaScript on the server
Node.js runs JavaScript outside the browser. Learn modules, npm, the file system, HTTP servers, events, async patterns, Express routing and middleware, environment variables and building a REST API.
Version control for every developer
Git tracks changes to your code and lets teams work together. Learn repositories, staging, commits, history, branches, merging, GitHub remotes, pull requests, undoing changes and .gitignore.
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