# 2021q1 Homework1 (culture)
contributed by < `tigger12613` >
> [作業要求](https://hackmd.io/@sysprog/linux2021-culture)

## 問題
* free software (自由軟體) 和 open source (開放原始碼) 兩者的理念有何落差？
* [free software 定義(by Free Software Foundation)](http://www.gnu.org/philosophy/free-sw.html.en)，代表使用者擁有執行、複製、散布、研究、更動和改善該軟體的自由。
* [open source 定義(by Open Source Initiative)](https://opensource.org/osd)
* [free software 解釋與 open source 的差別 ](http://www.gnu.org/philosophy/open-source-misses-the-point.html)As far as we know, all existing released free software source code would qualify as open source. Nearly all open source software is free software, but there are exceptions. First, some open source licenses are too restrictive, so they do not qualify as free licenses. For example, “Open Watcom” is nonfree because its license does not allow making a modified version and using it privately. Fortunately, few programs use such licenses.
* FSF 所提倡的 “Copyleft” 概念，和 “Copyright” 是否衝突？在實務上如何達成？free software 和 open source 的授權條款是否符合著作權精神呢？
* [What is Copyleft?](https://www.gnu.org/licenses/copyleft.en.html) Copyleft is a general method for making a program (or other work) free.
* Copyleft 是建立在 Copyright 之上的概念，因為 Copyright 提供作者對於作品的權力， 作者用 Copyright 的權力，主動把自己的權力分享出去，並且要求使用者必須以相同的授權分享使用到 Copyleft 授權的作品。
* 大部分的 free software lincenses 都有使用到 Copyleft 的內容。像是 GNU General Public License
* open source lincenses 則不一定有用到，像是 BSD lincense, MIT License 都不是 Copyleft。