Lightweight OSes/Windows XP alternatives

DeLi(cate) is a fork of DeLi Linux 0.8 targeted at very old and low RAM computers. It also works very efficiently on ordinary computers where you want to run lightweight applications and avoid the bulk of ordinary distributions. Minimum requirements are i386 or compatible, 8 MB RAM and 300 MB hard drive. Package management system is similar to Arch Linux.

Semplice Linux is a simple, fast and lightweight distribution based on Debian's unstable branch. It includes a small collection of up-to-date applications running on top of the Openbox window manager.

wattOS is a fast desktop Linux distribution based on Ubuntu. Using the lightweight Openbox window manager as its default user interface, the distribution strives to be as energy-efficient as possible so that it can be used on low-specification and recycled computers.

Slax is a minimalist desktop live CD based on Debian's "stable" branch, it boots into a simple desktop using the Fluxbox window manager which offers a small collection of applications.

Damn Small Linux is a very versatile 50MB mini desktop oriented Linux distribution.

Damn Small is small enough and smart enough to do the following things:

* Boot from a business card CD as a live linux distribution (LiveCD)
* Boot from a USB pen drive
* Boot from within a host operating system (thats right, it can run inside Windows)
* Run very nicely from an IDE Compact Flash drive via a method we call "frugal install"
* Transform into a Debian OS with a traditional hard drive install
* Run light enough to power a 486DX with 16MB of Ram
* Run fully in RAM with as little as 128MB (you will be amazed at how fast your computer can be!)
* Modularly grow -- DSL is highly extendable without the need to customize

DSL was originally developed as an experiment to see how many usable desktop applications can fit inside a 50MB live CD. But over time, Damn Small Linux grew into a community project with hundreds of development hours put into refinements including a fully automated remote and local application installation system and a very versatile backup and restore system which may be used with any writable media including a hard drive, a floppy drive, or a USB device.

Bodhi Linux is a lightweight Linux distribution based on Ubuntu that uses the Moksha Desktop environment.

antiX is a fast, lightweight and easy to install systemd-free Linux live CD distribution based on Debian Stable for Intel-AMD x86 compatible systems.

Tiny Core Linux (TCL) is a minimal Linux operating system that manifests the Core Project's philosophy and focuses on providing a base system using BusyBox and flwm. Its main features include an original minimal system structure that has only 2 folders, a quick and resourceful no-install mode that relies on running the system in RAM, easy system maintenance tools and fully modular extensions. The lead developer of the project is Robert Shingledecker. The distribution is notable for its size under 12 Megabytes, with additional functionality provided by extensions of which there are more than 3200. Tiny Core Linux is Free open source software and is licensed under the GNU General Public License v2.

Linux Lite is a beginner-friendly Linux distribution based on Ubuntu LTS and featuring the Xfce desktop.

Peppermint was designed for enhanced mobility, efficiency and ease of use. While other operating systems are taking 10 minutes to load, you are already connected, communicating and getting things done. And, unlike other operating systems, Peppermint is ready to use out of the box. Why spend hours tinkering and tweaking? Install Peppermint and get going!

Fast and powerful operating system based on the latest technologies while offering highly productive desktop environment. We focus on security, reliability, long-term stability and conservative integration of verified new features.

Trisquel is a computer operating system, a GNU + Linux distribution, derived from another distribution, Ubuntu, which is derived from Debian.

SliTaz is a free operating system, working completely in RAM and booting from removable media such as a CD-ROM or USB key. SliTaz is distributed as a LiveCD, and weighs less than 40MB. The system is quick and responsive, clean and robust. SliTaz is simple and intuitive, providing a lightweight, elegant desktop, detailed documentation and easy to use configuration tools.

Root filesystem taking up about 100 MB and ISO image of less than 40 MB.
Ready to use Web/FTP server powered by Busybox with CGI support.
Browse the Web with Midori, Firefox or Lynx in text mode.
Sound support provided by Alsa mixer, audio player and CD ripper/encoder.
Chat, mail and FTP clients.
SSH client and server powered by Dropbear.
Database engine with SQLite.
Generate a LiveUSB device.
Tools to create, edit or burn CD or DVD images.
Elegant desktop with Openbox running on the top of Xorg/Xvesa (X server).
Homemade graphical boxes to command line utilities.
4967 packages easily installable from the mirror.
Active and friendly community.

MX Linux is an operating system - a cooperative venture between the antiX and former MEPIS communities. It is a midweight OS that combines an elegant and efficient desktop with simple configuration, high stability and solid performance.

Linux is a free operating system, and Puppy Linux is a special build of Linux meant to make computing easy and fast.

Haiku is an open-source operating system that specifically targets personal computing. Inspired by the BeOS, Haiku is fast, simple to use, easy to learn and yet very powerful.

ReactOS™ is an Open Source effort to develop a quality operating system that is compatible with applications and drivers written for the Microsoft® Windows™ NT family of operating systems (NT4, 2000, XP, 2003, Vista, Seven).

The ReactOS project, although currently focused on Windows Server 2003 compatibility, is always keeping an eye toward compatibility with Windows Vista and future Windows NT releases.

The code of ReactOS is licensed under GNU GPL 2.0.

ReactOS is currently an Alpha quality operating system. This means that ReactOS is under heavy development, things may not work well and it can corrupt the data present on your hard disk. It is recommended to test ReactOS on a virtual machine or on a computer with no sensitive or critical data!