open source kernel

See the following -

What Do We Mean When We Talk About Software 'Alternatives'?

The word alternative is one of those shifty terms, with a definition that changes depending on perspective. For instance, something that is alternative to one person is the norm for another. Generally, the term alternative is considered to be defined by the fact that it is not considered to be in the majority or the mainstream. Then again, sometimes the term "alternative" gets attached to the second instance of something. If a web server, such as Apache, exists, then any time a different web server gets mentioned, it gets the alternative badge, because we all assume that we all silently concede that whatever it is, it's an alternative to that big one that we all know about...