Not necessarily cost-free
Commercial use is allowed. Support, deployment and hosting can still carry charges.
FinFly Explains / IT
Open source is about licence rights
OSI’s definition requires more than visible source code: redistribution and modification rights matter.
Read the licence
FinFly recommends checking the specific obligations, including redistribution of changes. Licences are not interchangeable.
Not a security certificate
Readable source can be inspected; it does not prove an audit happened. Check maintenance and dependencies separately.
Method
Primary sources
The explainer is checked against these institutional and industry sources. Links open the original material.