By Ashraf Al Shafaki
Content created by any person is automatically considered copyrighted except if the person who has created such content specifies otherwise. If that person who has created the content works for some company, that company may own the copyright of the content he has created.
Copyrighted content include:
Unless the creator of the content explicitly specifies that his or her content is not copyrighted and he releases it under an open license, you will not be able to use such content without an express written permission from the copyright owner.
There exists several types of licenses for created content. Each of those different licenses provide different permissions: