Open source is a philosophy, with participants believing in the free and open sharing of information in pursuit of the greater common good.
Open source refers to the open nature of a software or code, which are deemed by the copyright holders or the creators to be open for inspection, duplication and modification. Being open source allows users to use, analyze, modify, change and distribute the software or the code, as per their requirements and needs, for anything without restrictions. This ensures that end-users are able to use the software freely without having to face any lawsuit or other liabilities from the original developers. However, open source doesn’t necessarily mean free, and developers can still charge for services, namely consultancy and troubleshooting, among others.