A note before you begin
This article is general information, not legal advice. Copyright and related rules differ from one country to another, and a license is a legal document. If a lot of money or an important relationship depends on your choice, ask a qualified person where you live. The goal here is to help you understand the vocabulary so you can read the options sensibly.
Why a license matters
When you post a design, drawing, model file or piece of code online, you usually keep the copyright by default in many places. That means people may be unsure whether they are allowed to copy it, change it, print it or sell things made from it. A license answers those questions in advance. Without one, a careful person may simply decide not to use your work, which is probably not what you wanted when you shared it.
A license does not hand over ownership. You remain the author. You are telling others the conditions under which they may use your work.
What a license usually covers
Most licenses you will meet deal with a handful of questions:
- Copying and sharing. May others pass the files on?
- Modifying. May they change the design and share the changed version?
- Commercial use. May they sell things made from it?
- Credit. Must they name you?
- Conditions on what comes next. Must changed versions be shared on the same terms?
Different licenses answer these in different ways. Reading the actual text, or at least the official plain-language summary, matters more than guessing from a nickname.
Common families of licenses
Permissive licenses. These let people do almost anything, often with only a requirement to keep a credit or notice. They are common for code. People can use your work in their own projects, including ones they sell, without having to share their changes.
Share-alike (sometimes called copyleft) licenses. These let people use and change your work, but if they share their version, they must do so under the same terms. The idea is that improvements flow back to everyone. The trade-off is that some people avoid them because they do not want to be bound by the same conditions.
Creative-works licenses with a menu of options. A well-known set of public licenses lets creators combine choices: credit required or not, commercial use allowed or not, changes allowed or not, and share-alike or not. Makers often use them for photos, written instructions and some model files. Their terms are written for creative works, so some people prefer separate licenses for code or hardware.
Non-commercial terms. These forbid selling or commercial use. They sound simple, but “commercial” can be hard to define. A school that charges for a class, a makerspace that sells printed parts to cover costs, or a hobbyist who sells at a craft fair might all be unsure whether they qualify. If you choose such a term, think about the gray areas you would not want to argue about later.
Public-domain style dedications. These aim to give up as many rights as the law allows. Some places treat this differently, so such dedications often come with a fallback license.
Licenses written for hardware. Because copyright mainly covers creative expression rather than useful objects, hardware raises particular questions. Some licenses are written specifically with designs and manufactured products in mind. The idea of open hardware is covered in its own article, but the point here is that a license written for software may not fit a physical product perfectly.
Standard “all rights reserved”. You can keep full rights and only allow people to look. That is a legitimate choice, but it should be a deliberate one.
Separate licenses for separate parts
A single project often contains several kinds of material, and one license may not suit all of it:
- Documentation and photos may use a creative-works license.
- Code may use a software license.
- Design files such as drawings or circuit schematics may use a license suited to hardware or to creative works.
Say clearly which license applies to which folder or file. A short “License” note at the top of the project, plus a license file in the files themselves, avoids confusion.
Questions to ask yourself
- Do I want people to sell things made from my design?
- Do I want to be named?
- Do I want improved versions to be shared back?
- Am I building on someone else’s work? If so, their license may limit what I can choose.
- Might I want to sell this design or its products myself later? Giving broad rights to everyone can limit certain options.
Your answers matter more than any rule of thumb. If you used someone else’s files as a starting point, check their terms first, because a share-alike requirement may apply to your version.
What a license does not do
A license does not make a design safe. If you share instructions for something that could hurt people, a license will not protect them or you. Patents, trademarks and product safety rules are separate matters; a copyright-style license does not settle them. Basic intellectual property ideas and product liability questions are worth reading about if you plan to sell. A license also does not enforce itself: if someone ignores it, your options depend on local law and may be slow or costly.
Practical steps
- Choose before you post, not afterward.
- Use a well-known, existing license rather than inventing wording.
- Put the license name and a link to its official text next to your files.
- Add your name and the year so people know who to credit.
- If you change your mind later, remember that copies already shared under the old terms generally stay under those terms.
If you are unsure, a widely used license with a plain-language summary is usually a better starting point than custom wording. And if the stakes are high, a short consultation with a qualified person is cheaper than a dispute.