Please License Your Code
Code without a license isn’t open source. It isn’t free software, either.
Posting your code publicly doesn’t inherently apply a license to it.
Adding a license really isn’t hard – it’s just a label that clarifies the owner’s intent to share it.
Imagine you come into the school cafeteria and there’s a plate of cookies just sitting on one of the tables. No sign on it, no indication of what they’re for, but they’re out there in public. Is it ok to take one?
If you know the person who brought them, you can just ask if you can have one, and they’ll probably say yes. If some stranger brought them, then maybe they’re to share – you can, and many people would, certainly take your chances and have one anyway.
But what if they were put there by someone with malicious intentions and access to unpleasant chemicals, or even just baked by someone well-meaning but with extremely bad kitchen hygiene?
Or maybe the art club has been making realistic cardboard cookies for an upcoming play, or the veterinary students decided to decorate some dog biscuits all festively, or... you get the idea.
You can, and many people would, just take your chances and have a cookie. Most of the time, they’re as wholesome and delicious as they look and were put there by a nice person with a clean kitchen who intended to put a sign on them but was just busy and forgot to, or assumed that everyone would know. But every once in a while, that isn’t the case, and then the aftermath involves some awkward conversations or serious discomfort or even lawyers.
Applying an appropriate license to your open source code is effectively just putting a label by that plate of tasty solutions you’ve brought to the internet, saying who they’re for.
Note
I am not a lawyer. I am not your lawyer. Please do not try to eat software, regardless of how it’s licensed.