What's the difference between ubuntu-mate and ubuntu? [duplicate]

What is MATE DE?

quoting from the MATE Wikipedia article

MATE is a desktop environment forked from the now-unmaintained code base of GNOME 2. It is named after the South American plant Yerba mate and tea made from the herb, mate. The use of a new name, instead of GNOME, avoids conflicts with GNOME 3 components.

But what is a Desktop Environment?

quoting from the Desktop Environment Wikipedia article

In computing, a desktop environment (DE) is an implementation of the desktop metaphor made of a bundle of programs running on top of a computer operating system, which share a common graphical user interface (GUI).

A desktop environment typically consists of icons, windows, toolbars, folders, wallpapers and desktop widgets.

In Linux there are many different DEs. The most well-known are: Unity, GNOME 3, KDE, Cinnamon, XFCE, and LXDE.

So what is Ubuntu MATE?

quoting from the official Ubuntu MATE site

A community developed Ubuntu based operating system that beautifully integrates the MATE desktop.

Ubuntu MATE is a stable, easy-to-use operating system with a configurable desktop environment. Ideal for those who want the most out of their desktops, laptops and netbooks and prefer a traditional desktop metaphor. With modest hardware requirements it is suitable for modern workstations and older hardware alike.

So what is the difference between Gnome and MATE?

MATE is a fork of Gnome 2 and retains features from Gnome 2 such as the file manager, appearance preferences, panel and indicator function(re-branded) and is not interchangeable with GNOME Classic.

The forked programs have been renamed, with most names in Spanish.

• Caja (box) – File manager (from Nautilus)
• Pluma (quill) – Text editor (from Gedit)
• Eye of MATE – Image viewer (from Eye of GNOME)
• Atril (lectern) – Document viewer (from Evince)
• Engrampa (staple) – Archive manager (from File Roller)
• MATE Terminal – Terminal emulator (from GNOME Terminal)
• Marco (frame) – Window manager (from Metacity)
• Mozo (waiter) – Menu item editor (from Alacarte)

MATE DE (Desktop Environment) is a piece of software separate from Ubuntu, originally a fork of the older GNOME 2.x DE.

Ubuntu MATE, on the other hand, is (from the official page) "A community developed Ubuntu based operating system that beautifully integrates the MATE desktop."

Basically, MATE is the DE - it provides the GUI functionality.

Ubuntu MATE, on the other hand, is a derivative of Ubuntu, a sort of "child OS" based off Ubuntu, but with changes to the default software and design, most notably the use of the MATE DE instead of the default Ubuntu DE, Unity.

Source: What is Ubuntu MATE? | Ubuntu MATE