Open-source software is a shared-based model where developers of an application provide the full codebase for a project instead of only a compiled project with executable files. Microsoft is one of the most popular closed-source developers, but they have moved to an open-source model with some of their software projects in recent years. Open-source projects allow other developers to add to existing code, modify it, copy it, and analyse it for any cybersecurity and bug issues.

Open-Source Software versus Closed-Source Software

In the 1990s, when desktop computers became popular, software developers provided disks with compiled code that could be installed onto the user’s computer. Compiled code includes files with instructions that allow an operating system to dedicate computer resources and execute developer procedures. The byte code (for interpreted languages) or opcode (for compiled languages) is the language that computers can understand, and it’s used to carry out developer instructions.

As an example, the following code could be a part of a codebase:


if (active)
//do something


Humans easily understand this small snippet of pseudocode, but computers don’t understand human languages. Computers understand ones and zeros, so developers use compilers to convert the human language code into executables. Executables are used by the operating system to allocate memory, initialise variables, data, and the opcodes that make up the program itself. Compiled files are specific to an operating system because each operating system has different ways to make calls to internal procedures.

Because executables are compiled, humans cannot understand the instructions in the executable file. If you only have executable files, you cannot see the code itself unless you have a good de-compiler. This protects the copywritten developer code that cannot be analysed or stolen by a third party.

Open-source communities work differently by freely disclosing an application’s source code. The idea is that while the code could be stolen, the benefit of sharing code for analysis and expansion is far greater. Users can freely see the code to learn from it or improve upon it. Open-source code can be forked, which means another developer takes a copy of it and adds features to it. Some analysts review code for potential bugs and cybersecurity vulnerabilities and alert the original developer.

Just because open-source software developers publish their code does not mean it can be freely copied and used. Open-source developers define the type of license that applies to their code when the codebase is published. Licensing in the open-source world is similar to closed-source licenses in that licenses define the way code can be used, copied, changed, and distributed. For instance, some open-source licenses allow academics, students, and individuals to freely use code, but businesses must not use the codebase in commercial applications.

How Open-Source Works

The way developers create code for open-source projects is the same as closed-source, except projects are made public. Github is a common repository management platform ingrained in the development process. Like many code repository tools, it keeps a history for each project, allowing developers to roll back changes, check out code, and publish updates. Developers usually develop code in private, and then they publish changes to Github’s public cloud platform.

When a development project is public, other users can see every file relevant to the project. Users can download the repository as a whole, or each file can be viewed and downloaded separately. A full project download can be used to compile and run it on a user’s local machine so that it can be reviewed. Any bugs or difficulties with running the code can then be fixed in the user’s local copy.

The main developer for a project maintains, approves changes, and has full control of the codebase. Other users can take a copy, but the owner must approve any changes to the main codebase before they can be incorporated. The Linux operating system has several contributors to the code, but Linus Torvalds – the owner of the main codebase – must approve these changes.

A main codebase can be forked, which means the original owner of the project allows other developers to take a copy of the code and make changes to it. These changes aren’t incorporated into the main codebase. The changes are used to create a modified version of the software. For instance, the Linux operating system has several other versions such as Kali, Ubuntu, and Red Hat that use the core Linux operating system, but the modified versions have different pre-packaged tools and GUIs unique to the developer.

Benefits of Open-Source Software

With more contributors to the codebase, the software has better features, fewer bugs, and continual updates. It allows small developers to compete with more prominent brands by giving them a platform to distribute software and share it with others who can help improve it. For developers, it’s a great way to learn coding standards and identify better ways to code a particular procedure.

For users, most of the benefits lie with the stability and security of code. Users receive a compiled version of code that runs on their local machines, but with so many developers contributing, fewer bugs are likely. Cybersecurity analysts commonly download code to review it and alert developers of problems. Bigger open-source developers publish projects on whitehat hacking sites where they pay hackers to find vulnerabilities in their code. Using paid hackers results in open-source software that contains fewer vulnerabilities, which protects users from malicious attackers and malware that exploit unknown issues.

Major software such as operating systems that stay open-source makes it easier for developers to port their software from one operating system to another. With Windows, developers are tied to the latest operating system updates and changes and only know if their software will work on the latest changes by testing the code on the most recent version. With Linux, developers can more easily convert existing code that runs on Windows with the Linux operating system.

Why Is Open-Source Preferred?

End users are unaware if software is open-source versus closed-source. Most users think of open-source as free software, but that’s not always the case. For the individual using it for personal reasons, many open-source developers offer it for free and take donations, but users should always check licensing before freely installing software on a machine. License violations can be especially expensive for businesses that misuse open-source software.

Even if open-source software is not free, it’s usually much more affordable than closed-source software. Open-source developers typically make their money by offering support for a price. Large developers of popular Linux operating system distributions offer enterprise support with commercial software, and it’s how these developers stay in business and make money. Corporations get affordable software with paid support that could be much more cost-friendly than closed-source products.

Other researchers and IT professionals prefer open-source operating systems for different reasons. Linux has commands that the Windows operating system does not offer. Since Linux can be customised, there are fewer limitations than the Windows operating system. Hacks have been made available to alter the Windows operating system, but doing so violates the acceptable usage licensing provided by Windows. Usually, updates to the operating system overwrite unapproved custom changes, so it’s useless to make hacked changes to the operating system code.

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