What these mean, and how to choose

MIT

What it isThe most permissive standard open-source license. You allow anyone to do literally anything with your code.
RequiresKeep the copyright notice in the source.
Choose ifYou care about people using your code, not controlling it. Perfect for utilities, snippets, and things you want other developers to steal and build on.

CC BY-NC

What it isCreative Commons, Attribution-NonCommercial. You allow people to remix, learn from, and share your work.
RequiresCredit you, and never charge money for it.
Choose ifYou want a community to build on your work, but you want to reserve the right to sell it yourself one day.

CC BY-NC-SA

What it isCreative Commons, Attribution-NonCommercial-ShareAlike. The "pay it forward" license.
RequiresCredit you, no money, and anything built on top of it must use this exact same license.
Choose ifYou want to build a commons. This prevents someone from taking your free work, changing one line, and locking it up in a proprietary product.

CC0

What it isPublic Domain Dedication. You surrender all copyright.
RequiresNothing. No credit needed, no restrictions at all.
Choose ifYou're putting tiny tools out into the world and genuinely don't care who does what with them.

All Rights Reserved

What it isStandard copyright. You keep everything.
AllowsPeople can view the source to learn, but cannot copy, redistribute, or modify it.
Choose ifThis is a portfolio piece, or you plan to sell this work commercially later. It lets people admire it without legally taking it.
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