A Linux distribution is an operating system made from a software collection that includes the Linux kernel and often a package management system. Linux users usually obtain their operating system by downloading one of the Linux distributions, which are available for a wide variety of systems ranging from embedded devices and personal computers to powerful supercomputers.
z/OS is a 64-bit operating system for IBM z/Architecture mainframes, introduced by IBM in October 2000. It derives from and is the successor to OS/390, which in turn was preceded by a string of MVS versions. Like OS/390, z/OS combines a number of formerly separate, related products, some of which are still optional. z/OS has the attributes of modern operating systems but also retains much of the older functionality that originated in the 1960s and is still in regular use—z/OS is designed for backward compatibility.
GNU GRUB is a boot loader package from the GNU Project. GRUB is the reference implementation of the Free Software Foundation's Multiboot Specification, which provides a user the choice to boot one of multiple operating systems installed on a computer or select a specific kernel configuration available on a particular operating system's partitions.
VM is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible systems, including the Hercules emulator for personal computers.
Multi-booting is the act of installing multiple operating systems on a single computer, and being able to choose which one to boot. The term dual-booting refers to the common configuration of specifically two operating systems. Multi-booting may require a custom boot loader.
CRUX is a lightweight x86-64 Linux distribution targeted at experienced Linux users and delivered by a tar.gz-based package system with BSD-style initscripts. It is not based on any other Linux distribution. It also utilizes a ports system to install and upgrade applications.
Puppy Linux is a family of light-weight Linux distributions that focus on ease of use and minimal memory footprint. The entire system can be run from random-access memory (RAM) with current versions generally taking up about 600 MB (64-bit), 300 MB (32-bit), allowing the boot medium to be removed after the operating system has started. Applications such as AbiWord, Gnumeric and MPlayer are included, along with a choice of lightweight web browsers and a utility for downloading other packages. The distribution was originally developed by Barry Kauler and other members of the community, until Kauler retired in 2013. The tool Woof can build a Puppy Linux distribution from the binary packages of other Linux distributions.
TrueOS is a discontinued Unix-like, server-oriented operating system built upon the most recent releases of FreeBSD-CURRENT.
A portable application, sometimes also called standalone, is a program designed to operate without changing other files or requiring other software to be installed. In this way, it can be easily added to, run, and removed from any compatible computer without setup or side-effects.
A live USB is a portable USB-attached external data storage device containing a full operating system that can be booted from. The term is reminiscent of USB flash drives but may encompass an external hard disk drive or solid-state drive, though they may be referred to as "live HDD" and "live SSD" respectively. They are the evolutionary next step after live CDs, but with the added benefit of writable storage, allowing customizations to the booted operating system. Live USBs can be used in embedded systems for system administration, data recovery, or test driving, and can persistently save settings and install software packages on the USB device.
Software remastering is software development that recreates system software and applications while incorporating customizations, with the intent that it is copied and run elsewhere for "off-label" usage. The term comes from remastering in media production, where it is similarly distinguished from mere copying.
Wubi is a free software Ubuntu installer, that was the official Windows-based software, from 2008 until 2013, to install Ubuntu from within Windows, to a single file within an existing Windows partition.
The Linux booting process involves multiple stages and is in many ways similar to the BSD and other Unix-style boot processes, from which it derives. Although the Linux booting process depends very much on the computer architecture, those architectures share similar stages and software components, including system startup, bootloader execution, loading and startup of a Linux kernel image, and execution of various startup scripts and daemons. Those are grouped into 4 steps: system startup, bootloader stage, kernel stage, and init process. When a Linux system is powered up or reset, its processor will execute a specific firmware/program for system initialization, such as Power-on self-test, invoking the reset vector to start a program at a known address in flash/ROM, then load the bootloader into RAM for later execution. In personal computer (PC), not only limited to Linux-distro PC, this firmware/program is called BIOS, which is stored in the mainboard. In embedded Linux system, this firmware/program is called boot ROM. After being loaded into RAM, bootloader will execute to load the second-stage bootloader. The second-stage bootloader will load the kernel image into memory, decompress and initialize it then pass control to this kernel image. Second-stage bootloader also performs several operation on the system such as system hardware check, mounting the root device, loading the necessary kernel modules, etc. Finally, the first user-space process starts, and other high-level system initializations are performed.
The Red Hat Kickstart installation method is used by Fedora, Red Hat Enterprise Linux and related Linux distributions to automatically perform unattended operating system installation and configuration. Red Hat publishes Cobbler as a tool to automate the Kickstart configuration process.
NimbleX is a small Slackware-based Linux distribution optimized to run from a CD, USB drive or a network environment. NimbleX has been praised for how fast it boots, as well as for its small disk footprint, which is considered surprising for a distribution using KDE as desktop environment. NimbleX was also remarked for its website that allows users to generate custom bootable images by using a web browser. It was also covered in mainstream Romanian press as the first Linux distribution put together by a Romanian.
Qubes OS is a security-focused desktop operating system that aims to provide security through isolation. Isolation is provided through the use of virtualization technology. This allows the segmentation of applications into secure virtual machines called qubes. Virtualization services in Qubes OS are provided by the Xen hypervisor.
Ventoy is a free and open-source utility used for creating bootable usb media storage device with files such as .iso, .wim, .img, .vhd(x), and .efi files. Once Ventoy is installed onto a USB drive, there is no need to reformat the disk to update it with new installation files; it is enough to copy the .iso, .wim, .img, .vhd(x), or .efi file(s) to the USB drive and boot from them directly. Ventoy will present the user with a boot menu to select one of these files.
The Linux kernel can run on a variety of devices made by Apple, including devices where the unlocking of the bootloader is not possible with an official procedure, such as iPhones and iPads.
