The confusion among these kinds of software is incredibly common, even among the tech guys. It's important to have these concepts clear because they have very precise and important differences.
A Free Software is a software that you can use, share, modify and distribute. The source code of the software is open and you often get it free of charge. The most important point of Free Software is freedom. To get into more details, read the article What is Free Software.
Open Source uses the model of software development from Free Software and makes it more attractive to business. The important thing about Open Source is that the source code is open and allows cooperation, just like Free Software. The main difference between them is that the focus of Open Source is not freedom, it's business. For a more detailed definition you can read our article What is Open Source.
Because they are similar, Free Software and Open Source are sometimes called “FOSS” (Free and Open Source Software). They are both very different from the other types of software we will discuss next.
Freeware on the other hand is a software that is free of charge but has restricted rights. The “free” in freeware is not about freedom, it's about money. Thus it does not mean you can share or modify it. The source code of the program is usually not revealed (is closed) and you cannot distribute it (it has to be distributed by the company who owns it).
There are many other categories of software similar to freeware that are loosely defined. Shareware for example is a software that you can use free of charge with some limitations. Sometimes your right to use it is limited in time or it displays advertisement when you use it. With a shareware you have to pay to unlock its limitations. With commercial-ware you have to pay upfront to use the software. Malware is malicious software intended to harm your computer, files or privacy... Tupperware is a... no, that's something else. Well, let's summarize:
|FREE SOFTWARE||OPEN SOURCE||FREEWARE|
Let me give some examples to illustrate. VLC is a Free Software, you can download it, use it, share it, view its source code, modify the source code and share your modifications. Quicktime, Windows media player and Real player are freeware because, although you can download and use them for free, only the companies that own the software can distribute and modify it.
I know the difference might not be evident just by looking at the application. You have to look at the license of the software to know if it is FOSS or proprietary. Most FOSS are under a GPL license. Most proprietary software will display its license when you install and ask you to accept it. You have to accept the license before using proprietary software because it's your freedom that is at stake and they need your consent. Nobody reads those several pages long licenses (except lawyers maybe) but they are talking about the freedoms you do not have with the software. Think about it next time you accept one!
To find Free and Open Source Software to download, try out our custom Search for FOSS. Hopefully you will find there the software you need!