Firefox OS is a Linux kernel-based mobile operating system designed for smartphones, tablets and smart TVs.
The operating system is developed by the open source community of the Mozilla Foundation, best known for the Firefox browser. Design and development are based entirely on open standards and non-proprietary technologies.
The browser-based operating system was developed with HTML5, CSS, JavaScript and C++. A web-based user interface called Gaia runs on top of the Firefox OS stack, which includes the operating system layer, known as Gonk. Gecko, a layout engine, reads various types of content -- HTML or JavaScript, for example -- and renders it for the user. The system is designed to work with HTML5 apps, which are build with responsive web design (RWD) to be device-agnostic.
The first version of Firefox OS, released in mid-2013, was created for low-end phones to make them more accessible for people with limited means. Since that time, developers have added features to make the system more competitive with well-established mobile operating systems such as Android and iOS. Alcatel, Huawei, LG, Nexus and ZTE are among the vendors that have released Firefox OS devices.
Firefox OS was called Boot to Gecko (B2G) in the initial development project.
Mozilla explains the concepts behind Firefox OS: