The Remix IDE is a fully fledged online development environment which lets you write, test, deploy and invoke Smart Contracts right from the comfort of your browser.
It has support for different Solidity compiler versions, various plugins such as debuggers or linters as well as an in-browser CLI.
Protip 1: Did you stumble upon an interesting dApp project on GitHub you'd like to play around with? Simply use the "Import from GitHub" functionality and start coding within in seconds.
Protip 2: The Remix Project offers a Remix Desktop App which helps you develop your Smart Contracts in an offline-ready IDE. No need to install and configure compilers, editors and plugins.
- Ethereum Foundation