Copyright is an economic right that gives you the opportunity to make commercial gain from the exploitation of your works. This is generally done by licensing the right to use the work to clients.
[hidden title="About copyright"]
Copyright is an area which is governed by the Copyright, Designs and Patents Act, 1988. When you create a collage, painting, drawing, diagram, map, chart, plan, engraving, etching, lithograph, woodcut or similar work, you have created an artistic work and that is protected by copyright, provided that your illustrations fall into any one of these categories.
As creator of that illustration you own the copyright which subsists in it. There are no registration requirements and no requirement to use the © sign, although used online it will help the public to realise that your illustration is protected by copyright.
There is one exception to this general rule. If you are an employee and your job requires you to create illustrations, then usually your employer will own the copyright in these works.
[hidden title="Copyright and licensing"]
If you own copyright, you are the only person who has the right to make copies of your illustrations. If someone else makes a copy without your permission, they are infringing your copyright.
Copyright in your illustration is an economic right. It is different from ownership of the physical illustration itself (if you create physical artwork).
You can give permission to individuals or companies to reproduce your illustration, which is known in the illustration trade as granting a licence. Your licence should be in writing and should set out the use that can be made of your illustration, the territory it is used in and the duration of the licence, and also any restriction you wish to place on the use. You can grant licences for different uses. See Writing a Licence.
[hidden title="Selling your copyright"]
Although this is generally not recommended, you can sell your copyright, which means that you have no further right of reproduction in your work. This is known as an assignment, but will only be effective if you put it in writing. Copyright is a very valuable commodity. It affords the owner the exclusive right to reproduce an image (or sell on to allow others to reproduce it) in any way throughout the world for the period of copyright. If a client wants you to assign copyright in your commissioned artwork they must be prepared to pay a sum that reflects all the possible uses they could put the artwork to.
With US clients you may asked to agree to a work-for-hire (or work made for hire) contract. While this may sound innocuous, it is in fact an American legal term which means that the commissioner will own the copyright in the work, rather than the creator. This should be resisted unless the fee is appropriate for this significant right.
For it to be binding, the illustrator and client must agree in a contract that it is a work made for hire. As it is an assignment, the points above apply.
[hidden title="Copyright Infringement"]
If your illustration is reproduced without your permission, you are entitled to damages; perhaps an injunction to stop the infringement and on occasion the infringing copies delivered to you. See Going to Law.