Wikipedia
Maemo is a software platform developed by Nokia and then handed over to Hildon Foundation for smartphones and Internet tablets. The platform comprises both the Maemo operating system and SDK.
Maemo is mostly based on open-source code and has been developed by Maemo Devices within Nokia in collaboration with many open-source projects such as the Linux kernel, Debian, and GNOME. Maemo is based on Debian GNU/Linux and draws much of its GUI, frameworks, and libraries from the GNOME project. It uses the Matchbox window manager and the GTK-based Hildon framework as its GUI and application framework.
The user interface in Maemo 4 is similar to many hand-held interfaces and features a "home" screen, from which all applications and settings are accessed. The home screen is divided into areas for launching applications, a menu bar, and a large customizable area that can display information such as an RSS reader, Internet radio player, and Google search box. The Maemo 5 user interface is slightly different; the menu bar and info area are consolidated to the top of the display, and the four desktops can be customized with shortcuts and widgets.
At the Mobile World Congress in February 2010, it was announced that the Maemo project would be merging with Moblin to create the MeeGo mobile software platform. Despite that, the Maemo community continued to be active, and in late 2012 Nokia began transferring Maemo ownership to the newly established Hildon Foundation.