Copyright is an artificial concept that gives the creator of a work, or the person he sells the right to, the legal right to use or modify in whole or in part, and to call their own.  It has a different meaning in most jurisdictions, however the basic principle is the same: the creator owns the original copyright to the work in question, and has the freedom to pass this on at will, usually in consideration for money.  Where a creator is working on commission, copyright is designed to act as a lien in his favour, meaning that if he creates and passes on but does not receive payment, he can withhold copyright and sue for breach where applicable.  Of course, he would also have remedies under the ordinary law of contract, but the grasp of copyright is a very powerful tool, which can even be used against the third party buyer from the original commissioner.

Copyright is designed as a tool to cover what is known as intellectual property.  Committing intellectual thoughts and ideas to paper, or making them tangible is usually sufficient to give rise to the copyright protection, which usually lasts for a number of decades in preventing others from steeling ideas.  This is primarily designed to encourage forward thinking and art, and can be a vital tool in protecting the financial interests of those responsible for some of the world's most vital progressions.  Consider the inventors of the seatbelt, Volvo.  Volvo could have used their copyright to prevent other manufacturers from installing seat belts, and this would have been sufficient to protect any other manufacturer from doing so.  Of course they waived their rights for the safety of the general public, which is also a possible consideration for the creator of something new and innovative.

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