The most important things you need to know are
- everything in 2sxc is open source and free
- 2sxc itself is licensed under the extremely permissive MIT license
- 2sxc contains many, many other third party components which are also open source.
- The licenses used range from AGPL (very copyleft) to X11 (aka MIT, very free).
- Most of the components use very permissive licenses (like MIT or Apache 2.0)
- A few components contain copyleft requirements - this is especially relevant for the Image Resizer
So in summary: if you want to create open-source work, you can stop reading now - or just donate something for a good cause. If you don't want to share your work with others, please read on...