Unit 1: Chapter 5 : IT Resources

  IT Resources

Open-source software (OSS) is any computer software that's distributed with its source code available for modification. That means it usually includes a license for programmers to change the software in any way they choose: They can fix bugs, improve functions, or adapt the software to suit their own needs.Open source software is software with source code that anyone can inspect, modify, and enhance.

"Source code" is the part of software that most computer users don't ever see; it's the code computer programmers can manipulate to change how a piece of software—a "program" or "application"—works. Programmers who have access to a computer program's source code can improve that program by adding features to it or fixing parts that don't always work correctly.

Other popular open-source software is:

·         Mozilla's Firefox web browser.

·         Thunderbird email client.

·         PHP scripting language.

·         Unix OS

·         Apache HTTP web server.

      There are open source software applications for a variety of different uses such as office automation, web design, content management, operating systems, and communications.

Open source software can have a major impact on your entire organization. There are several advantages of using open source software. 

Advantages :

1.      Lesser hardware costs

Since Linux and open source solutions are easily portable and compressed, it takes lesser hardware power to carry out the same tasks when compared to the hardware power it takes on servers, such as, Solaris, Windows or workstations. With this less hardware power advantage, you can even use cheaper or older hardware and still get the desired results.

2.      High-quality software

Open source software is mostly high-quality software. When you use the open source software, the source code is available. Most open source software are well-designed. Open source software can also be efficiently used in coding. These reasons make open source software an ideal choice for organizations.

3.      Integrated management

By using open source software, you can benefit from integrated management. Open source software uses technologies, such as, common information model (CIM) and web based enterprise management (WBEM). These high-end technologies enable you to integrate and combine server, application, service and workstation management. This integration would result in efficient administration.

4.      Simple license management

When you use open source software, you would no longer need to worry about licenses. Open source software enables you to install it several times and also use it from any location. You will be free from monitoring, tracking or counting license compliance.

5.      Lower software costs

Using open source software can help you minimize your expenses. You can save on licensing fees and maintenance fees. The only expenses that you would encounter would be expenditure for documentation, media and support.
What is an Operating System?

Every time you switch on your computer, you see a screen where you can perform different activities like write, browse the internet or watch a video. What is it that makes the computer hardware work like that? How does the processor on your computer know that you are asking it to run a mp3 file?
Well, it is the operating system or the kernel which does this work. A kernel is a program at the heart of any operating system that takes care of fundamental stuff, like letting hardware communicate with software.
So, to work on your computer, you need an Operating System(OS). In fact, you are using one as you read this on your computer. Now, you may have used popular OS's like Windows, Apple OS X but here we will learn what Linux is and what benefits it offers over other OS choices.

An operating system has three main functions:

 (1) Manage the computer's resources, such as the central processing unit, memory, disk drives, and printers,

 (2) Establish a user interface, and

 (3) Execute and provide services for applications software.

Types Of OS : 

1. Windows Operating System

Windows is a series of operating systems developed by Microsoft. Each version of Windows includes a graphical user interface, with a desktop that allows users to view files and folders in windows. For the past two decades, Windows has been the most widely used operating system for personal computers PCs.

The Windows operating system (Windows OS) for desktop PCs are more formally called Microsoft Windows and is actually a family of operating systems for personal computers. Windows dominates the personal computer world, running, by some estimates, more than 90 percent of all personal computers – the remainder running Linux and Mac operating systems. Windows provides a graphical user interface (GUI), virtual memory management, multitasking, and support for many peripheral devices. In addition to Windows operating systems for personal computers, Microsoft also offers operating systems for servers and mobile devices.

Windows OS Quick Links

·         MS-DOS

·         Windows 1.0 - 2.0

·         Windows 3.0 – 3.1

·         Windows 95

·         Windows 98

·         Windows ME - Millennium Edition

·         Windows NT 31. - 4.0

·         Windows 2000

·         Windows XP

·         Windows Vista

·         Windows 7

·         Windows 8

·         Windows 10

2. Linux OS

Linux is an operating system or a kernel. It is distributed under an open source license. Its functionality list is quite like UNIX.

Who created Linux?

Linux is an operating system or a kernel which germinated as an idea in the mind of young and bright Linus Torvalds when he was a computer science student. He used to work on the UNIX OS (proprietary software) and thought that it needed improvements.

However, when his suggestions were rejected by the designers of UNIX, he thought of launching an OS which will be receptive to changes, modifications suggested by its users. So Linus devised a Kernel named Linux in 1991. Though he would need programs like File Manager, Document Editors, Audio -Video programs to run on it. As time passed by, he collaborated with other programmers in places like MIT and applications for Linux started to appear. So around 1991, a working Linux operating system with some applications was officially launched, and this was the start of one of the most loved and open-source OS options available today.

The earlier versions of Linux were not so user-friendly as they were in use by computer programmers and Linus Torvalds never had it in mind to commercialize his product.

This definitely curbed the Linux's popularity as other commercially oriented Operating System Windows got famous. Nonetheless, the open-source aspect of the Linux operating system made it more robust.

The benefits Linux

The main advantage of Linux was that programmers were able to use the Linux Kernel to design their own custom operating systems. With time, a new range of user-friendly OS's stormed the computer world. Now, Linux is one of the most popular and widely used Kernel, and it is the backbone of popular operating systems like Debian, Knoppix, Ubuntu, and Fedora. Nevertheless, the list does not end here as there are thousands of OS's based on Linux which offer a variety of functions to the users.

Linux now enjoys popularity at its prime, and it's famous among programmers as well as regular computer users around the world. Its main benefits are -

It offers a free operating system. You do not have to shell hundreds of dollars to get the OS like Windows!

• Being open-source, anyone with programming knowledge can modify it.
• The Linux operating systems now offer millions of programs/applications to choose from, most of them free!
• Once you have Linux installed you no longer need an antivirus! Linux is a highly secure system. More so, there is a global development community constantly looking at ways to enhance its security. With each upgrade, the OS becomes more secure and robust
• Linux is the OS of choice for Server environments due to its stability and reliability (Mega-companies like Amazon, Facebook, and Google use Linux for their Servers). A Linux based server could run non-stop without a reboot for years on end.

* Difference Between Unix and Linux

UNIX is called the mother of operating systems which laid out the foundation to Linux. Unix is designed mainly for mainframes and is in enterprises and universities. While Linux is fast becoming a household name for computer users, developers, and server environment. You may have to pay for a Unix kernel while in Linux it is free.

But, the commands used on both the operating systems are usually the same. There is not much difference between UNIX and Linux. Though they might seem different, at the core, they are essentially the same. Since Linux is a clone of UNIX. So learning one is same as learning another. 

3. DOS (Disk Operating System)

 DOS is an operating system that runs from a hard disk drive. The term can also refer to a particular family of disk operating systems, most commonly MS-DOS (Microsoft Disk Operating System).

An operating system (OS) is the software that controls a computer's hardware and peripheral devices and allows other programs to function. Early computers did not have disk drives but were hard-wired to carry out specific computations. Later, computers were able to store instructions loaded into the computer's memory using punch cards and later magnetic tapes. Computer memory space was limited and when the instructions to control a computer were moved onto a disk drive, such as a floppy disk or internal hard drive, it was considered cutting-edge technology. Today, any modern operating system would be considered a disk operating system.