What is Linux ?

Just like Windows XP, Windows 7, Windows 8, and Mac OS X, Linux is an operating system. An operating system is software that manages all of the hardware resources associated with your desktop or laptop. To put it simply – the operating system manages the communication between your software and your hardware. Without the operating system (often referred to as the “OS”), the software wouldn’t function.

 we use the term “Linux” to refer to the Linux kernel, but also the set of programs, tools, and services that are typically bundled together with the Linux kernel to provide all of the necessary components of a fully functional operating system. Some people, particularly members of the Free Software Foundation, refer to this collection as GNU/Linux, because many of the tools included are GNU components. However, not all Linux installations use GNU components as a part of their operating system. Android, for example, uses a Linux kernel but relies very little on GNU tools.


Who “owns” Linux?

By virtue of its open source licensing, Linux is freely available to anyone. However, the trademark on the name “Linux” rests with its creator, Linus Torvalds. The source code for Linux is under copyright by its many individual authors, and licensed under the GPLv2 license. Because Linux has such a large number of contributors from across multiple decades of development, contacting each individual author and getting them to agree to a new license is virtually impossible, so that Linux remaining licensed under the GPLv2 in perpetuity is all but assured.

How was Linux created?

Linux was created in 1991 by Linus Torvalds, a then-student at the University of Helsinki. Torvalds built Linux as a free and open source alternative to Minix, another Unix clone that was predominantly used in academic settings. He originally intended to name it “Freax,” but the administrator of the server Torvalds used to distribute the original code named his directory “Linux” after a combination of Torvalds’ first name and the word Unix, and the name stuck.

How does Linux differ from other operating systems?

In many ways, Linux is similar to other operating systems you may have used before, such as Windows, OS X, or iOS. Like other operating systems, Linux has a graphical interface, and types of software you are accustomed to using on other operating systems, such as word processing applications, have Linux equivalents. In many cases, the software’s creator may have made a Linux version of the same program you use on other systems. If you can use a computer or other electronic device, you can use Linux.

But Linux also is different from other operating systems in many important ways. First, and perhaps most importantly, Linux is open source software. The code used to create Linux is free and available to the public to view, edit, and—for users with the appropriate skills—to contribute to.

Linux is also different in that, although the core pieces of the Linux operating system are generally common, there are many distributions of Linux, which include different software options. This means that Linux is incredibly customizable, because not just applications, such as word processors and web browsers, can be swapped out. Linux users also can choose core components, such as which system displays graphics, and other user-interface components.

Who uses Linux?

You’re probably already using Linux, whether you know it or not. Depending on which user survey you look at, between one- and two-thirds of the webpages on the Internet are generated by servers running Linux.

Companies and individuals choose Linux for their servers because it is secure, and you can receive excellent support from a large community of users, in addition to companies like Canonical, SUSE, and Red Hat, which offer commercial support.

Many of the devices you own probably, such as Android phones, digital storage devices, personal video recorders, cameras, wearables, and more, also run Linux. Even your car has Linux running under the hood.

The OS is comprised of a number of pieces:

The Bootloader: The software that manages the boot process of your computer. For most users, this will simply be a splash screen that pops up and eventually goes away to boot into the operating system.

The kernel: This is the one piece of the whole that is actually called “Linux”. The kernel is the core of the system and manages the CPU, memory, and peripheral devices. The kernel is the “lowest” level of the OS.

Daemons: These are background services (printing, sound, scheduling, etc) that either start up during boot, or after you log into the desktop.

The Shell: You’ve probably heard mention of the Linux command line. This is the shell – a command process that allows you to control the computer via commands typed into a text interface. This is what, at one time, scared people away from Linux the most (assuming they had to learn a seemingly archaic command line structure to make Linux work). This is no longer the case. With modern desktop Linux, there is no need to ever touch the command line.

Graphical Server: This is the sub-system that displays the graphics on your monitor. It is commonly referred to as the X server or just “X”.

Desktop Environment: This is the piece of the puzzle that the users actually interact with. There are many desktop environments to choose from (Unity, GNOME, Cinnamon, Enlightenment, KDE, XFCE, etc). Each desktop environment includes built-in applications (such as file managers, configuration tools, web browsers, games, etc).

Applications: Desktop environments do not offer the full array of apps. Just like Windows and Mac, Linux offers thousands upon thousands of high-quality software titles that can be easily found and installed. Most modern Linux distributions (more on this in a moment) include App Store-like tools that centralize and simplify application installation.

How can I get started using Linux?
There’s some chance you’re using Linux already and don’t know it, but if you’d like to install Linux on your home computer to try it out, the easiest way is to pick a popular distribution that is designed for your platform (for example, laptop or tablet device) and give it a shot. Although there are numerous distributions available, most of the older, well-known distributions are good choices for beginners because they have large user communities that can help answer questions if you get stuck or can’t figure things out. Popular distributions include Debian, Fedora, Mint, and Ubuntu, but there are many others.

How to Install Kali Linux Step by Step ?

Kali Linux is a Debian based operating system, arguably one of the finest pentesting and security auditors reliable OS loaded with hundreds of renowned security related tools.

Installation Requirements

• Minimum 20 GB of free space in your hard drive is recommended.
• Minimum 1 GB of ram, recommended: 2 GB or more in Hard Disk install or dual boot installation but if you are opting for installing it with virtualization in your current OS (Virtual Box) then at least 4 GB of ram is recommended.
• CD-DVD Drive / USB Support

Installation Procedure

First Download Kali Linux from Official Website.

Step 1 : Boot your PC with Kali Linux once booted, Select Graphical Install.

Step 2 : Select your preferred language.

Step 3 : Select your geographical location.

STEP 4 : Select the preferred keyboard.

STEP 5 : Let Kali be your Hostname & hit continue.

STEP 6 : You may optionally provide a default domain name for this system to use or you can keep it blank and can hit on conitnue.

STEP 7 : Set a password for your Kali Machine & hit continue.

Step 8 : The installer will now offer you four choices about the partitions of the disk. 

In our case, we are using the entire disk on our computer and not configuring LVM (logical volume manager). Experienced users can use the “Manual” 

partitioning method for more granular configuration options.

Step 9 : Select the partitioning disk, recommended option is all files in one partition for new users & then hit on continue.

Step 10 : Select finish partitioning and write changes to disk then hit continue 

-> Select Yes to write changes to the disk and click on continue

Let it install the system automatically, this may take a while…

Step 11 : Configure network mirrors. Kali uses a central repository to distribute applications, select Yes on mirror network & hit on continue.

--> keep HTTP proxy information blank on next screen and hit continue.

Let it configure the package manager related files then…

Step 12 : Install the grub boot loader manually so select Yes & hit on continue.

Step 13 : Select the hard-disk to install which means select 2nd option where the hard disk path is given as we are not going to enter a device manually & then hit on continue.

Step 14 : Finally, click on continue to finish the installation, it will install some final stage files and after it is completely done, your security related weapons loaded Kali is ready to roll!

Log into Kali Linux with the username and password.

Computer Basics. No experience necessary.

Gain the skills and knowledge required to operate your computer and perform common tasks. Learn basic computer skills the smart way with Computer Basics training courses at CCE, the University of Sydney.

This basic computer skills course will allow you to gain an understanding of the most popular, current technologies used at home and in the workplace. You will become computer literate in this hands-on course while you learn to access, create, save and manage documents, spreadsheets and emails and use the Internet effectively. We demystify terminology and impart best practice skills for productive and secure use of hardware and software. This course is great for adults with no previous computer experience.

Aims
This course will allow you to become familiar with computers and Microsoft Windows while learning basic computer, mouse and keyboard skills in a supportive classroom environment.

Outcomes

Upon successful completion of this course, participants should be able to:Appropriately start up and shut down their computer.Navigate the operating system and start applications.Perform basic functions of file management.Perform basic functions in a word processor and spreadsheet.Manage print settings and print documents.Receive and send emails.Use a web browser to navigate the Internet.

What is Computer?

       “A Computer is an electronic machine that can solve different problems, process data, store & retrieve data and perform calculations faster and efficiently than humans”.

           You may already know that you can use a computer to type documents, send email, play games, and browse the Web. You can also use it to edit or create spreadsheets, presentations, and even videos.

What are the different types of computers?

When most people hear the word computer, they think of a personal computer such as a desktop or laptop. 

However, computers come in many shapes and sizes, and they perform many different functions in our daily lives. When you withdraw cash from an ATM, scan groceries at the store, or use a calculator, you're using a type of computer.

    The Basic Hardwere?    

    Hardware in the context of technology, refers to the physical elements that make up a computer or electronic system and everything else involved that is physically tangible. This includes the monitor, hard drive, memory and the CPU. Hardware works hand-in-hand with firmware and software to make a computer function. 

And software, hardware is a collective term. Hardware includes not only the computer proper but also the cables, connectors, power supply units, and peripheral devices such as the keyboard, mouse, audio speakers, and printers.

 How to Buying a Computers?

 First to know when you buy a PC, it can be from a reputed brand such as Dell, HP, Asus or Lenovo. Whereas, if you build the PC, you can make it with your own choice of parts, from scratch.

Factors to consider when buying or building a PC

   If you decide to buy or build your pc, consider the following factors:

• Budget

-  Be careful and realistic to keep the budget in check.

-   Do your research on the brands using online forums, reviews in magazines and so do to get the best deal.