What distinguishes open-source software from proprietary software?

When we talk about the differences between **open-source software** and **proprietary software**, there are a few key points to understand:

1. Cost:
- **Open-source software** is usually available for **free**. This means you can download, use, and share it without paying any money.
- **Proprietary software**, on the other hand, often requires a **purchase** or a subscription fee. You have to pay to use or access its features.

2. Security:
- There is a common perception that **open-source software** can be **more secure**. This is because anyone can review the code for bugs and vulnerabilities, which can be fixed quickly by the community.
- With **proprietary software**, the source code is typically kept secret, limiting who can examine the code and fix issues. Security updates are dependent on the company providing the software.

3. Freedom to Modify:
- **Open-source software** is very flexible because it allows users to **modify and redistribute** the software. This means that anyone with programming skills can change the software to suit their needs and share those modifications with others.
- **Proprietary software** does not generally allow users to modify or distribute the software. It comes with restrictions that limit how you can use and share it.

In summary, **open-source software** offers **freedom, flexibility, and cost advantages** but comes with the need for technical expertise to ensure security. Meanwhile, **proprietary software** provides **structure and convenience** with potential costs and usage restrictions.