Unity is a graphical shell originally developed by Canonical Ltd. for its Ubuntu operating system. It debuted in 2010 in the netbook edition of Ubuntu 10.10 and was used until Ubuntu 17.10. Following its discontinuation by Canonical in 2017, development of forks of Unity7 and Unity8 has continued – the latter was renamed Lomiri in February 2020.
Unity7 is the default desktop environment in Ubuntu Unity, an official flavor of Ubuntu since 2022. The maintainers of Ubuntu Unity and Unity7 have started working on the successor of Unity7, UnityX.
It was part of the Ayatana project, an initiative with the stated intention of improving the user experience within Ubuntu. It was initially designed to make more efficient use of space given the limited screen size of netbooks, including, for example, a vertical application switcher called the launcher, and a space-saving horizontal multipurpose top menu bar. Unlike GNOME, KDE Plasma, Xfce, or LXDE, Unity is not a collection of applications. It is designed to use existing programs.
Features
The Unity user interface consists of several components: Top menu bar: a multipurpose top bar, saving space, and containing: the menu bar of the active application the title bar of the main window of the active application, including the maximize, minimize and exit buttons the session menu, including the global system settings, logout, and shut down the diverse global notification indicators including the time, weather, and the state of the underlying system. Launcher: a taskbar. Multiple instances of an application are grouped under the same icon, with an indicator showing how many instances are open. The user has a choice whether or not to lock an application to the launcher. If it is not locked, an application may be started using the Dash or via a separately installed menu. Quicklist: the accessible menu of launcher items Dash: a desktop search utility that enables searching for information both locally (e.g. installed applications, recent files, or bookmarks) and online (e.g. Twitter or Google Docs). It displays previews of the results. Head-up display (HUD): Allows hotkey searching for top menu bar items from the keyboard, without the need for using the mouse, by pressing and releasing the Alt key. Indicators: a notification area containing the clock, network status, battery status, and audio volume controls
Dash
Dash is a desktop search utility with preview ability. It enables searching for applications and files. Dash supports search plug-ins, known as Scopes (formerly Lenses). Out of the box, it can query Google Docs, Ubuntu One Music Store, YouTube, Amazon, and social networks (for example, Twitter, Facebook, and Google+). Starting with Ubuntu 13.10, online search queries are sent to a Canonical web service which determines the type of query and directs them to the appropriate third-party web service. Pornographic results are filtered out.
One of the new features of Unity in Ubuntu 12.10 is the shopping lens. As of October 2012, it sent search terms from the user's home lens to Canonical's servers via HTTPS, which would forward them to Amazon which, as part of the search process, sends images of matching products to the lens via HTTP, with Canonical receiving a small commission upon a sale.
Many reviewers criticized it: as the home lens is the natural means to search for content on the local machine, reviewers were concerned about the disclosure of queries that were intended to be local, creating a privacy problem. The feature is active by default (instead of opt-in) and many users could be unaware of it.
On 23 September 2012, Mark Shuttleworth defended the feature. He posted "the Home Lens of the Dash should let you find *anything* anywhere" and that the shopping lens is a step in that direction. He argued that anonymity is preserved because Canonical servers mediate the communication between Unity and Amazon and users could trust Ubuntu. Ubuntu Community Manager Jono Bacon posted "These features are neatly and unobtrusively integrated into the dash, and they not only provide a more useful and comprehensive dash in giving you visibility on this content, but it also generates revenue to help continue to grow and improve Ubuntu." Steven J. Vaughan-Nichols from ZDNet said the feature does not bother him and wrote "If they can make some users happy and some revenue for the company at the same time, that's fine by me." Ted Samson at InfoWorld reported the responses from Shuttleworth and Bacon, but he still criticized the feature.
On 29 October 2012, the Electronic Frontier Foundation criticized the problem. It argued that since product images were (as of October 2012) returned via insecure HTTP then a passive eavesdropper—such as someone on the same wireless network—could get a good idea of the queries. Also, Amazon could correlate the queries with IP addresses. It recommended Ubuntu developers make the feature opt-in and make Ubuntu's privacy settings more fine-grained. It noted that the Dash can be stopped from searching the Internet by switching off "Include online search results" in Ubuntu's privacy settings.
On 7 December 2012, Richard Stallman claimed that Ubuntu contains spyware and should not be used by free software supporters. Jono Bacon rebuked him; he said that Ubuntu responded and implemented many of the requirements the community found important.
Since September 2013, images are anonymized before being sent to the user's computer.
A legal notice in the Dash informs users of the sharing of their data. It states that unless the user has opted out, by turning the searches off, their queries and IP address will be sent to productsearch.ubuntu.com and "selected third parties" for online search results. Ubuntu's Third Party Privacy Policies page informs all of the third parties that may receive users' queries and IP addresses, and states: "For information on how our selected third parties may use your information, please see their privacy policies."
Soon after being introduced, doubts emerged on the conformance of the shopping lens with the European Data Protection Directive. By late 2013, these doubts made the grounds for a formal complaint on the shopping lens filed with the Information Commissioner's Office (ICO), the UK data privacy office. Almost one year later the ICO ruled in favour of Canonical, considering the various improvements introduced to the feature in the meantime to render it conformal with the Data Protection Directive. However, the ruling also made clear that at the time of introduction the feature was not legal, among other things, since it lacked a privacy policy statement.
In March 2014, Michael Hall speaking for Canonical Ltd, indicated that in Unity 8 users will have to opt-in for each search, which will be conducted by opening a special scope and then choosing where to search, addressing previous criticism of its functionality. As of April 2016, with the release of Ubuntu 16.04 LTS, the setting is off by default.
Unity 2D
Initially Canonical maintained two discrete versions of Unity, which were visually almost indistinguishable but technically different.
Unity is written as a plugin for Compiz and uses an uncommon OpenGL toolkit called Nux. Being a plugin for Compiz gives Unity GPU-accelerated performance on compatible systems. It is written in the programming languages C++ and Vala.
Unity 2D was a set of individual applications:File:Unity-2D Natty.png developed for environments that Compiz does not run on, such as when graphics card does not support OpenGL. They were written in the GUI building language QML from the widespread Qt framework. By default Unity 2D used the Metacity window manager but could also use accelerated window managers like Compiz or KWin. In Ubuntu 11.10, Unity 2D used Metacity's XRender-based compositor to achieve transparency effects. Starting with Ubuntu 11.10, Unity 2D replaced the classic GNOME Panel as the fall-back for users whose hardware could not run the Compiz version of Unity.
Unity 2D was discontinued for the release of Ubuntu 12.10 in October 2012, as the 3D version became more capable of running on lower-powered hardware.
Availability As Unity and the supporting Ayatana projects are developed primarily for Ubuntu and Ubuntu was the first to offer new versions.
Outside of Ubuntu, other Linux distributors have tried to pick up Ayatana, with varying success. The Ayatana components require modification of other applications, which increases the complexity for adoption by others. Arch Linux offers many Ayatana components, including Unity and Unity 2D, via an unofficial repository or through AUR. Fedora does not offer Unity in its default repositories because Unity requires unsupported patches to GTK. However Unity 6 has been ported to Fedora 17 and can be installed through a branch in the openSUSE repositories where the patches are applied. Newer Fedora and Unity versions are not supported. Frugalware had adopted Ayatana, including Unity and Unity 2D, as part of the development branch for an upcoming Frugalware release but the project is no longer maintained. openSUSE offers many Ayatana components for GNOME. After the packager abandoned the project because of problems with the then-current version of Compiz, new developers picked up the task and provide packages for openSUSE 12.2 (along with versions for Arch Linux and Fedora 17). Newer openSUSE and Unity versions are not supported. Manjaro has a Unity version of its distribution. Ubuntu Unity uses the Unity 7 desktop. Gentoo has a community-supported overlay to build the Unity7 interface.
Development Unity was originally unveiled on 10 May 2010 during Ubuntu founder Mark Shuttleworth's keynote at the Ubuntu Developer Summit in Brussels. It was announced as the new interface of both Ubuntu Netbook Edition and a then-planned OEM platform called Ubuntu Light. The new interface was also made available for download during the keynote and visitors of the summit could try it out on a Dell Mini 10v. Shuttleworth cited philosophical differences with the GNOME team over the user experience to explain why Ubuntu would use Unity as the default user interface instead of GNOME Shell, beginning April 2011, with Ubuntu 11.04 (Natty Narwhal). Jono Bacon later explained that Ubuntu will continue to function with the GNOME interface with Unity as a variant of it.
Canonical announced it had engineered Unity for desktop computers as well and would make Unity the default shell for Ubuntu in version 11.04. GNOME Shell was not included in Ubuntu 11.04 Natty Narwhal because work on it was not completed at the time 11.04 was frozen, but was available from a PPA, and was available in Ubuntu 11.10 and later releases, through the official repositories.
In November 2010, Mark Shuttleworth announced the intention to eventually run Unity on Wayland instead of the currently used X Window System, although this plan has since been dropped, replacing Wayland with Mir for Unity 8. (2013)
In December 2010, some users requested that the Unity launcher (or dock) be movable from the left to other sides of the screen, but Mark Shuttleworth stated in reply, "I'm afraid that won't work with our broader design goals, so we won't implement that. We want the launcher always close to the Ubuntu button." However, with Ubuntu 11.10, the Ubuntu button was moved into the launcher. A third-party plugin that moved Unity 3D's launcher to the bottom was available. An option to move the launcher to the bottom of the screen was officially implemented in Ubuntu 16.04.
, the Unity shell interface developers use a toolkit called Nux instead of Clutter. Unity is a plugin of the Compiz window manager, which Canonical states is faster than Mutter, the window manager for which GNOME Shell is a plugin.