开源代码是否可以商用？
- 是否可以商用？
- 如何查看许可证是哪个？
- 什么是 Apache License 2.0 ？
- 如何使用开源代码？
- 1、根路径添加 LICENSE 文件
- 2、根路径添加 NOTICE 文件
- 3、在使用的地方（放在文件最上面）
- 参考地址
是否可以商用？
开源代码是否可以商用，其实是要看源代码的开源许可证，如果源代码对应的开源许可证是支持免费商用，当然可以用，但是一定要遵循其规定
如下部分许可证总结：
https://www.ruanyifeng.com/blog/2011/05/how_to_choose_free_software_licenses.html
常用开源协议以及是否能够商用：https://www.zhangbj.com/p/833.html
如何查看许可证是哪个？
找到其源码，阅读其源码仓库中的 LICENSE 文件
如果是 Apache License ，便可以商用，但是要遵循其规定。
什么是 Apache License 2.0 ？
Apache License 2.0协议来自于著名的Apache基金会，其最重要的开源软件就是Apache（HTTPD）网站服务器。
Apache License协议和BSD类似，同样鼓励代码共享和尊重原作者的著作权，同样允许代码修改，再发布（作为开源或商业软件）。需要满足的条件也和BSD类似：
- 需要给代码的用户一份Apache Licence
- 如果你修改了代码，需要在被修改的文件中说明
- 在延伸的代码中（修改和有源代码衍生的代码中）需要带有原来代码中的协议，商标，专利声明和其他原来作者规定需要包含的说明。
- 如果再发布的产品中包含一个Notice文件，则在Notice文件中需要带有Apache Licence。你可以在Notice中增加自己的许可，但不可以表现为对Apache Licence构成更改。
Apache Licence也是对商业应用友好的许可。使用者也可以在需要的时候修改代码来满足需要并作为开源或商业产品发布/销售。著名的Android系统，Apache基金会的众多开源项目，Swift项目等，都是用Apache Lincese 2.0协议。
使用Apache Licence 2.0协议的好处是:
- 永久权利，一旦被授权，永久拥有。
- 全球范围的权利，在一个国家获得授权，适用于所有国家。假如你在美国，许可是从印度授权的，也没有问题。
- 授权免费无版税， 前期、后期均无任何费用。
- 授权无排他性，任何人都可以获得授权
- 授权不可撤消，一旦获得授权，没有任何人可以取消。比如，你基于该产品代码开发了衍生产品，你不用担心会在某一天被禁止使用该代码。
转自：什么是Apache License 2.0开源协议：
如何使用开源代码？
1、根路径添加 LICENSE 文件
内容如下：
Apache License
Version 2.0, June 2018
http://www.apache.org/licenses/
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Licensed under the Apache License, Version 2.0 (the "License");
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.2、根路径添加 NOTICE 文件
我看一般开源项目里都没有这个文件，大家自行判断吧
用于记录第三方库
Apache SkyWalking
Copyright 2017-2020 The Apache Software Foundation
This product includes software developed at
The Apache Software Foundation (http://www.apache.org/).「Apache SkyWalking Copyright 2017-2020 The Apache Software Foundation」 对应的是第三方库：
Apache SkyWalking ：作者或者机构
Copyright
2017-2020
The Apache Software Foundation：项目
「This product includes software developed at The Apache Software Foundation (http://www.apache.org/).」
如上内容固定
3、在使用的地方（放在文件最上面）
Copyright 2019, hegaojian(何高建)
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.如果修改了源代码，需要在源代码内进行说明
参考地址
使用开源项目必须保留作者姓名？开源软件不能商用？我们需要先学会分辨开源许可证：https://zhuanlan.zhihu.com/p/368237701
本文章为转载内容，我们尊重原作者对文章享有的著作权。如有内容错误或侵权问题，欢迎原作者联系我们进行内容更正或删除文章。
