Open-source definition & meaning
Open-source means the source code which can be freely accessible for modification and redistribution. Open-source is mostly referred to as software. Most of the open-source software is also licensed with an open-source license such as MIT, GPL, Apache, BSD, etc. Open-source software may also be free software, depending on the license. Open-source software is popular because it is free to use, change or distribute. There are also different open-source operating systems such as Linux, Unix, BSD, and Solaris.
Plenty of commercial software may also be open-sourced. For example, Red Hat Enterprise and Oracle Linux are based on an open-source operating system, providing commercial subscription systems for the users.
The Internet is now full of open-source CMS software such as WordPress, Drupal, and Joomla. Also, it is very easy to find open-source e-commerce CMS like WooCommerce, OpenCart, or Magento. The database systems such as MySQL, PostgreSQL, and MariaDB are also open-source software. The open-source model is a decentralized software-development model which is based on open collaboration. Developers use project management systems and source code providers for efficient collaboration. GitHub, GitLab, and BitBucket are most the popular DevOps platforms.