Copyright was put into place to protect individual or company rights to a particular work that they have created that is unique.
This grants the creator of the work the exclusive rights to that piece so they have the ability to copy, produce and make changes to the work. This also protects them from others making a copy of their work and distributing it as their own work. In the event one finds an individual has stolen their work they can seek legal action against this person or company that is in violation of copyright laws. Generally you will find that a copyright will last between 50 and 100 years after a persons death.
If you are seeking to obtain a copyright it will differ from country to country. In the United States prior to 1989 any works that were published had to contain a copyright notice with the name of the author, date of publication and the holder of the copyright. This is now no longer required for a copyright.
When a violation of copyright has been detected it is a civil related court issue in most locations. However, some locations consider it to be a criminal act and will be handled in a criminal nature. This obviously makes a difference in the type of attorney you plan to hire because lawyers that deal with civil issues will have much different experience and knowledge than those that are knowledgeable as criminal defense lawyers. You will generally find that most all copyright issues are civil in nature with those that end up as criminal will usually involve some form of counterfeit action.
You will find the majority of copyright violations fall under the distribution of digital media and are shared on many file sharing websites. Most of these file sharing websites can’t have much legal action taken against them for several reasons. Most of the sites are hosted in countries that do not recognize copyright laws, so within their country there are no legal boundaries. In addition, actual legitimate file sharing sites are sometimes abused but will act swiftly in the removal of copyrighted files. They will unfortunately in most cases not reveal the information of the person who may have uploaded the file due to privacy laws. You will generally find that they will only provide assistance to law enforcement agencies looking for information. In the event you believe you were the victim of copyright infringement and see to talk with copyright lawyers you will find you are best to speak with others on who they would recommend to handle such a delicate issue for you.