Picking an open source licence

There's loads of licences out there. Here's a flowchart to help you choose:

1. Are you making software?
   • Yes: use 0BSD
   • No: use CC0

Why?

• It's the shortest one
• It lightens mental overhead for others
• It sends a message of trust: "I am not interested in suing you" and "I know you'll respect my work".

But people will use my code without crediting me

If they did, wouldn't it be a good problem? It means you've made something good enough to 'steal', and popular enough to 'steal', and you love it enough to care.

Cool people will credit you anyway.

If it still bugs you, use MIT or zlib. (If it's not software, use CC BY.)

But Microsoft can use my code to make bad stuff

Again, good problem to have.

The anti-Microsoft licence is GNU GPL. (For non-software, CC BY-SA works. CC BY-SA-NC is stricter, both for Microsoft and not-Microsoft.)

But what if it's used for military purposes?

There's a class of "ethical" licences that say things like "don't use this to oppress people" or "don't use this to pollute the environment". Unfortunately, they have a shaky legal foundation. TODO link?

Your best bet is GNU GPL again, because military purposes are likely to be closed-source. (Non-software: CC BY-SA or CC BY-SA-NC.)

Unfortunately, if they really want your code, they won't care and will use it anyway.