One of the biggest misconceptions of free and open-source software(FOSS) is that is free of cost. In reality, FOSS can have a monetary cost and still be fully compliant with the FOSS concept.
In order to be considered free software it has to respect the following four freedoms:
- Freedom 0: The freedom to run the program for any purpose.
- Freedom 1: The freedom to study how the program works, and change it to make it do what you wish.
- Freedom 2: The freedom to redistribute and make copies so you can help your neighbor.
- Freedom 3: The freedom to improve the program, and release your improvements (and modified versions in general) to the public, so that the whole community benefits.
Freedoms 1 and 3 require source code
to be available because studying and modifying software without its
source code can range from highly impractical to nearly impossible.
While some prefer keep the open-source part out, and just talk about free software, I prefer to the free and open-source software term since the source code needs to be available for software to be fully free. Specially when I talk about the subject with people who aren't versed on software development, since it helps to explain the concept in a more concise and in a way more readily understandable for people who aren't that much into software.
Personally, I've found the most people aren't aware that FOSS exist. Even when they use Firefox or Android(tough it has some proprietary components on some devices), they're unaware that FOSS is a viable alternative. Other popular, and robust FOSS include LibreOffice, GIMP and Ubuntu.
In a way, FOSS needs more mainstream promotion. Most of the time, most people seem to thing of FOSS of something only geeks and computer engineers can user. While some FOSS is aimed for those user, there are many others aimed for the average users. The most famous examples again would be Firefox and Android.
On the operating systems side, I can recommend to most users Ubuntu or Linux Mint, since I've used both of them and I've found them really easy to use. Both have all what the average user will ever need, and any extras can be easily found on the stores that both operating systems have.
FOSS has proven it's worth on the technical side, now the question is how to make the case for it's use to the average users. They are more than capable to use it, but there are many psychological barriers to be torn down, and some ease of access ones, before there will be more willingness to use it.
In the end, it's time to do some serious marketing aimed to a wider audience.