What is open source software?
Open source software (OSS) is a decentralized development model that distributes source code publicly for open collaboration and peer production known as “the open source way.”
Man working in a desktop computer
Open source vs closed source software

The open source way is a form of thinking and collaborating within the open source community. This philosophy is based on intellectual freedom and core principles: transparency, collaboration, delivery, inclusion, and community. The exchange of ideas and software developed by communities has driven creative, scientific, and technological advancement in such industries as: education, government, law, health, and manufacturing. This movement created a way for a global community to collaborate, share, and assist  both individual and group goals through source code.

Open source software is collaborative, relying on community production and peer review to use, change, and share source code with each other. Developers share insights, ideas, and code to create more innovative software solutions both collectively and individually. This scalable and flexible software ensures that anyone with the source code can modify, enhance, and redistribute it for better reusability and accessibility. Open source software operates with the underlying principles of peer production and mass collaboration, creating more sustainable software development for end users.  

Closed source software (CSS) is proprietary software that is not distributed to the public. The software is encrypted, so only the original authors who created the code exclusively have rights to legally copy, modify, update, and edit the source code. Closed software imposes restrictions on what the end user can do with the application, preventing users from modifying, sharing, copying, or republishing the source code.

In additional to open and closed source, FOSS (Free/Open Source Software) allows users access to software from a more philosophical perspective. Within FOSS, there is Free Software Foundation (FSF) to protect user freedoms and Open Source Initiative (OSI) to ensure the technical values of reliable software. There are a wide variety of free software licenses that can be used, modified, and sold commercially including: GPL, LGPL, and BSD licenses.

Some of the most popular open source software licenses include:

  • MIT License©: MIT License is a free software license that allows users to modify the original code with very few restrictions. 
  • GNU General Public© (GPL): The GNU is a series of free software licenses that guarantee end users the ability to run, study, share, and modify software. 
  • Apache®: The Apache License 2.0 is a free software license that allows users to use, modify, and distribute the software for any purpose. 
  • BSD: This license has fewer restrictions on developers, allowing users to use and modify the code without having to share modifications.
  • MySQL™: MySQL is an open-source database management system with two separate licenses - the MySQL Standard Edition and MySQL Enterprise Edition.
  • SUSE: SUSE Linux is built on top of open source Linux kernel and distributed with system and application software.
  • Ubuntu®: Ubuntu is a Linux distribution made of free and open source software released in desktop, cloud, and IoT.
Open Source Projects
History of Unix® and Linux

Unix development started in 1969 at AT&T® Bell Labs as a proprietary but licensable product.  For the next ten years, the development of Unix had multiple versions including V6, which became the first available outside of Bell Labs.

This code soon caught the attention of the academic community due to the nature of the new language. The University of California at Berkley started the development of its own Unix and soon developed an academic version called the Berkley Software Distribution (BSD license). Simultaneously, AT&T evolved their version of Unix into System V. These two versions eventually merged to create the unified seventh edition of Unix and then further evolved into such programs as: Sun Solaris, FreeBSD, NetBSD, and OpenBSD.

In 1984, Richard Stallman created a free Unix clone named GNU (GNU’s Not Unix). This version was open to be used freely, modified, and redistributed as needed. In 1991, Linus Torvalds created the operating system kernel known as “Linux” or the Linux kernel. Combined with FSF and BSD components, Linux became a fully operating system; it now runs on several architectures and has been adopted or supported by old-line Unix vendors.

Open source in enterprises

Enterprise open source is more than just open source, it’s an integration of a single permissively licensed open source library that is run on open source. To be enterprise open source, a product has to be tested, adjusted, and examined for security flaws by a security team who can respond to security issues. Enterprise open source also has convenient features, such as single sign-on (SSO) and integration with SSO platforms and directory management.

Enterprise IT environments require a lot of investment and planning, often making software outdated by the time that applications are installed. These applications also often require additional training and certifications, which are stated in the service agreements. However, enterprise open source has a predictable lifecycle with information and components that move at different speeds. The software has a long lifespan with important applications; for example, Red Hat® Enterprise Linux has a lifecycle of 10 years.   

Many companies and individuals prefer to use open source software over proprietary or commercial software due to its versatility, security, evolution, community, training, and stability.  Some advantages of using open source are: cost and savings, flexibility of customizing code, and freedom of leveraging a community instead of a single vendor. There are some disadvantages to open source, which include: subpar support, poor documentation, undue complexity, intrusive advertising, and vulnerabilities.

For those who still require proprietary software, there are the disadvantages to outdated software, bulk products, higher or unexpected costs, confusing licensing arrangements, and single vendor dependence.  However, some companies are drawn to a single vendor for one-stop shopping, scalable enterprise-grade products, professional interface, routine updates, no programming required, and integration with applications and products. 

History and evolution

Commitment to open source

Many enterprise companies like IBM have been committed to open source, from backing emerging communities to contributing to the development of licenses to advocating governance and standards.

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