Yes. An essential aspect to copyright is that every creative work will eventually fall into the "public domain." A public domain work occurs after a work has existed for a certain amount of time. Here's, however, where it get's really confusing: because copyright law has been extended (in law) a mere 11 times, it's not always clear whether a work is in the public domain. We'll cover this in more detail in the "public domain" section but the general rule of thumb is this: if it was published before 1923, it's in the public domain. If it was published after 1923, it may or may not be in the public domain. If it published after 1923, assume that it is still copyrighted unless there is clear evidence otherwise.
Another type of work that may not be totally copyrighted are Creative Commons works. Again, there will be more information about this later, but creative commons allows the creator to say how and to what extent their work is used. The effort of Creative Commons is to enable greater sharing and use of works created by someone else.