Musicians do make money and copyright plays a large part in their earnings. Copyright is a legal protection that protects the rights of authors of creative works, and includes the rights of composers. It is important, as fledging professional musicians yourselves, to take copyright seriously. Did you know that as soon as you write a composition, and have it notated in any format, that your work is automatically under copyright?
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There are general provisions in copyright law, called Fair Use provisions, that allow the use of copyrighted scores in educational pursuits. However, Fair Use does not allow for use of copyrighted works in many public performance settings, whether or not there is a charge to attend the performance, without the permission of the copyright holder. That said, scores you borrow from a library, or through Interlibrary Loan, do not come with automatic permission for use in a public performance. For more information, check out: