
When you purchase something, often you own physical property of some kind -- a car, some clothing, etc. If someone else wants to use your property, they must either purchase it from you or get your permission to borrow it.
Copyright signifies ownership of intellectual property. It protects works of original authorship. While facts and ideas cannot be copyrighted, creative expressions of one's ideas (words, photos, drawings, etc.) are protected by this law.
Copyright regulations also apply to:
In the United States, the Copyright Office (part of the Library of Congress) manages applications and keeps records for copyrights. Their online publication Copyright Basics provides an overview of the copyright law.
-- When Does Copyright Begin?
Works of expression are protected by copyright as soon as they are created and fixed in a tangible medium. When a work is entered into a computer in a form that can be read on a screen or routed to a printer, it is considered fixed.
-- How Is Copyright Indicated?
Copyright notices shown on printed publications or on the Web usually include the copyright symbol (©), the year of first publication and the name of the copyright owner, as shown in the illustration.
But here are two important facts to remember about copyright:
The same copyright laws that guide the "offline" world apply online as well. In practical terms, this means that works you find on the Net that don't have the typical copyright information displayed are most likely still protected.
The one area where copyright law does not apply is to works in the public domain. These are available for free use without restrictions. Works enter the public domain when:
The Creative Commons (CC) site helps you to find online resources (text, images, audio, video) that you can use, and even "remix" into something else, without violating copyright protections. When creators attach a Creative Commons license to their work, they indicate what is permitted (use the work, modify or adapt the work, etc.)
For a quick intro to Creative Commons, check out this short video, entitled "Wanna Work Together?" (3 minutes)
Video available in other formats here.

Use Creative Commons Search for this exercise.
Search for: "global warming"NOTE: Google Advanced Search also allows you to limit results by "Usage Rights."
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