What License Means What?

What Software License

Means What?

Madeline Bernard, 2/11/16

What License Means What?

Copyright is the default ¹

- As soon as you creatively express yourself, that expression is copyrighted. You don't have to file anything.

- Until 70 years after your death no one will be able to make copies of your stuff, or make it available, or make anything based off it. ²

- If you put your thing in a public GitHub repo, you have agreed to their TOS that you'll let people view it and make personal copies of it by forking.

1. Caveats: In the USA; also, I am not a lawyer

2. Except in cases of Fair Use, which may require painful court cases to establish

What License Means What?

@Mad_Bernard

Licenses: four basic options

Copyleft: use your copyright to say "you can only distribute/copy/build from this if you make your source code readable and it also uses these terms"

designed to stop corporations from hiding and not sharing

Open Source: anyone can build from your code

Public Domain: no copyrights, no caveats

in your package.json, put "license": "UNLICENSED"

What License Means What?

@Mad_Bernard

Copyleft / free software

GPL v2.0: the second most popular license. If the software can't be distributed freely, it can't be distributed at all.

GPL v3.0: the fourth most popular license. Has strong protections against being jerked around by patents. Legally supports the nerfing of DRM.

Affero General Public License, Version 3 (AGPL): like the GPL3, but makes it clear that internet code must also be shared.

LGPL: "Lesser" Gnu Public License: Weaker copyleft, invented to make it clear that linking to a library wasn't going to convert your code to copyleft.

Used by: MySQL, Linux, Drupal, WordPress

What License Means What?

@Mad_Bernard

Open source

MIT: the most popular license. Short and readable, it requires that you give credit to the person who made the thing you're using, and do not sue them.

BSD: like MIT, but older

Apache: second most popular open source license, third overall. It requires that you give credit, and mark any file where you've changed the previous code. It's popular because it has a patent grant and a retaliation clause: no one can sue you for using patents they brought into the project, and if they do, they lose access to the project.

Used by: Node.js, jQuery

Used by: Android OS

What License Means What?

@Mad_Bernard

Other

CC0 1.0: Public domain, even for countries that normally don't have that. Also includes "you can't sue me".

Dual Apache/MIT: compatible with GPL v3.0, protects against patent trolls, makes your thing available to the widest possible group of people, means that you can use Apache's credit-giving setup instead of MIT's "copy the license a zillion times" thing

A short discussion of the value of dual Apache/MIT:

https://github.com/PistonDevelopers/image-gif/issues/15

Used by: Rust

What License Means What?

@Mad_Bernard