When comparing Ubuntu MATE vs Puppy Linux, the Slant community recommends Puppy Linux for most people. In the question“What are the best Linux distributions for desktops?” Puppy Linux is ranked 10th while Ubuntu MATE is ranked 73rd. The most important reason people chose Puppy Linux is:
Puppy Linux requires 128MB of RAM and 333Mhz of CPU, although 256MB of RAM is recommended.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Simplicity of Gnome with the power of Ubuntu
Debian was good to use but has limited documentation and is difficult to pick up. Ubuntu MATE brings the ease of design and logic of the Gnome 2 style desktop so it's easy to get around coupled with the vast documentation, forums and ease of learning/using the Ubuntu system.
Pro Works great on old laptops
It does not have a lot of system requirements so it works pretty well even on older laptops.
Pro Perfect for people who like Gnome 2
The goal of MATE is to maintain the look and feel of Gnome 2, while maintaining compatibility with Gnome 3. To that end, it has also forked and renamed many of Gnome's core applications. It benefits from the years of work and polish that have gone into the Gnome project.
Pro Highly configurable
Comes with an option to configure as Windows-like, Mac-like, Gnome-like, etc. in a single click. Wonderful to get you started without having to learn it all from scratch.
Pro Behaves like Ubuntu with Unity - after Ubuntu-Gnome transformation
No better place to continue Unity experience with Ubuntu (Left-side panel, HUD) and not as awkward as Gnome.
Pro Based on Ubuntu
Pro Extremely low minimum system requirements
Puppy Linux requires 128MB of RAM and 333Mhz of CPU, although 256MB of RAM is recommended.
Pro The whole OS runs off of RAM
Since Puppy Linux is completely loaded and run off of RAM instead of HDD, it's read/write speed is not a factor.
Pro Designed to run as a live USB/CD
A portable version, that can be carried on a thumb drive without requiring installation, weighs less than 100MB; a Live CD - less than 150MB. You can even save your settings and files for Puppy on the external device/media.
Running off a live CD also has security benefits, as your system will reset to the known config after each boot.
Pro Different distro based versions available
Puppy Linux offers a few different releases.
The first is an Ubuntu based release called Tahrpup, by using this version the user is able to take advantage of all software and support from Ubuntu.
The second version is called Slacko, which is built upon the Slackware binaries.
The third is called Wary and it is built to support older hardware than the rest.
And the fourth is called Quirky, which is used as a base to explore new ideas.
Pro Linux distro designed for this exact purpose
Pro Offers a long term support release
Puppy Linux offers an LTS release called Precise.
Pro It can be the only distro that works
Sometimes, Puppy Linux is the only distro that works on an old machine: all other distros are more demanding.
Pro JWM used as window manager
JWM is a low resource window manager that is used in most Puppy Linux installs.
Cons
Con No very good Software Center by default
The Software Boutique is not good. You can install Gnome Software from it.
Con Too much bloat included by default
Con Redundant
There is absolutely no reason to install it, since it uses the same package repositories as Ubuntu and you can transform any Ubuntu install into a Ubuntu MATE install.
Con Not bleeding edge
Users who want the latest and greatest software would be happier using Arch Linux, Antergos or another rolling release distro. However, because Ubuntu MATE is based on Ubuntu, users still have access to a large repository of recent software.
Con A bit ugly
Using puppy makes you feel like you just jumped 20 years into the past. Being that the purpose of Puppy Linux is to run or really low resource machines the software used is often on the older side, which is precisely why it has a 20 year old look.

Con Not as light as it used to be
It's light, but not as light as it was 1-2 years ago.
Con Smallest software library ever
You can barely find any precompiled packages for Puppy.
Con No built in compositing
Being a low resource distro there is zero built in compositing for the JWM window manager. Though one can be added through a bit of work.
