- Boot & Reboot
- Boot Disk
- firmware
- Bootloader
- kernel
- device driver
- GNU
- GRUB
- CLI & GUI
- Unity
- GNOME
- Terminal/Console
- Root User
- Binaries
- Package Manager
- apt-get and rpm
In computing, booting is the process of starting a computer. It can be initiated by hardware such as a button press, or by a software command.
In computing, rebooting is the process by which a running computer system is restarted, either intentionally or unintentionally
Alternatively referred to as a startup disk, system disk, master disk, or bootabledisk, a boot disk is a storage device that contains special files required for the computer to boot into an operating system. It can be CD, HDD, USB or any other. If the bootable disk is removable media (e.g., USB or CD-ROM), it bypasses the hard drive, depending on the settings in the BIOS. This diskette is most often used to troubleshoot the computer or allow the user to copy files when a computer is down.
Firmware is a software program or set of instructions programmed on a hardware device. It provides the necessary instructions for how the device communicates with the other computer hardware. It is typically stored in the flash ROM of a hardware device. While ROM is "read-only memory," flash ROM can be erased and rewritten because it is actually a type of flash memory.
Every electronic devices e.g. microwave oven, AC, TV, Washing machine which have microcontroller must need a software to run it. I case of computer this Firmware is called BIOS or UFEI. which is stored in a BIOS chip inside it.
A bootloader is the first software that runs when a computer starts. It is typically started after the computer or the BIOS have finished performing the initial power and hardware device checks and tests.
It fetches the kernel from the hard disk or any specified boot device within the boot sequence, into the main memory.
An operating system can have single bootloader or multiple boot loader programs classified as primary and secondary boot loaders, where a secondary boot loader might be larger and more capable than the primary boot loader.
Basically It's a kind of bridge between Hardware and Software.
The kernel is the most important part of the operating system. It is the primary interface between the hardware and the processes of a computer. The kernel connects these two in order to adjust resources as effectively as possible.
While starting a computer after bootloader loads the kernel in computer's RAM then it (the kernel) initializes the rest of the operating system: shell, display manager, desktop environment, etc.
A device driver is a small piece of software that tells the operating system and other software how to communicate with a piece of hardware.
For example, printer drivers tell the operating system, and by extension whatever program you have the thing you want to print open in, exactly how to print information on the page
GNU stands for 'GNU's Not UNIX'. It is a UNIX like computer operating system, but unlike UNIX, it is free software and contains no UNIX code. It is pronounced as guh-noo. Sometimes, it is also written as GNU General Public License. It is based on the GNU Hurd kernel and It is intended to develop and share software for free, for all its users.
Grand Unified Bootloader or GRUB is a bootloader available from the GNU project. It is a complete program for loading and managing the boot process. It is the most common bootloader for Linux distributions.
If there occuers any trouble before loading the kernel, computer will enter in grub rescue mode shell where user have operate manually for further process of booting.
If we want to operate a machine we need a interface through which we can give instructions as input and get result as output. In computer we have two type of interface CLI (Command Line Interface) and GUI (Graphical User Interface)
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CLI - you may have seen a dark screen where where user have to put command to perform any task. Here we don't have any button or graphical design, e.g. Comand Prompt, PowerShell, BASH . The program which handles this interface is called a command-line interpreter or command-line processor. know more
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GUI - A graphical user interface is an interface program that allows users to interact with a computer through its graphic display like button, slide bar, icons, pointer etc. Everyting what you can interact with mouse except terminal is GUI.
Unity is a graphical shell for the GNOME desktop environment originally developed by Canonical Ltd. for its Ubuntu operating system, and now being developed by the Unity7 Maintainers and UBports. Unity debuted in the netbook edition of Ubuntu 10.10.
GNOME is a free and open-source desktop environment for Unix-like operating systems. It is an official flavor of Ubuntu, featuring the GNOME desktop environment. GNOME was originally an acronym for
GNU Network Object Model Environment, but the acronym was dropped because it no longer reflected the vision of the GNOME project.
In the linux world they can all look the same from the point of view of the user at the keyboard. The differences are in how they interact with each other.
The <b>shell</b> is the program which actually processes commands and returns output. Most shells also manage foreground and background processes, command history and command line editing. These features (and many more) are standard in bash, the most common shell in modern linux systems.
A <b>terminal</b> refers to a wrapper program which runs a shell. Decades ago, this was a physical device consisting of little more than a monitor and keyboard. As unix/linux systems added better multiprocessing and windowing systems, this terminal concept was abstracted into software. Now you have programs such as Gnome Terminal which launches a window in a Gnome windowing environment which will run a shell into which you can enter commands.
The <b>console</b> is a special sort of terminal. Historically, the console was a single keyboard and monitor plugged into a dedicated serial console port on a computer used for direct communication at a low level with the operating system. Modern linux systems provide virtual consoles. These are accessed through key combinations (e.g. Alt+F1 or Ctrl+Alt+F1; the function key numbers different consoles) which are handled at low levels of the linux operating system -- this means that there is no special service which needs to be installed and configured to run. Interacting with the console is also done using a shell program.
source: superuser.com
The root user, also known as the superuser or administrator, is a special user account in Linux used for system administration. It is the most privileged user on the Linux system and it has access to all commands and files. The root user can do many things an ordinary user cannot, such as installing new software, changing the ownership of files, and managing other user accounts.
Compiled computer programs are typical examples; indeed, compiled applications are sometimes referred to, particularly by programmers, as binaries. Binary files include image files, sound files, executable (i.e., runnable) programs and compressed data files. typically done by a linker. In computer science, a library is a collection of subroutines or classes used to develop software. Libraries contain code and data that provide services to independent programs.
A package manager is a tool to import external dependencies, package, software. We don’t have to reinvent the wheel and are able to make the most of the tools at your disposal. using any package manager we can install any program with a single command which makes our task easier. Like, in ubuntu using apt package manager we can install/uninstall/update/fix any program with a single command
apt-get is the command-line tool for handling packages, and may be considered the user's "back-end" to other tools using the APT library. Several "front-end" interfaces exist, such as synaptic and aptitude.
- Synopsis: apt-get [options] [-o config=string] [-c=cfgfile] command [pkg]
rpm is a powerful Package Manager, which can be used to build, install, query, verify, update, and erase individual .rpm software packages.