Well first off, if you don't have a copyright (which it doesn't sound like you do) - no, there's no purpose. A copyright is actual legal material which you have to apply for, just like a patent (http://www.copyright.gov/forms/). However whether this is worth it or not depends on the nature of what you're putting up online.
"A copyright notice or copyright symbol is an identifier placed on copies of the work to inform the world of copyright ownership. While use of a copyright notice was once required as a condition of copyright protection, it is now optional. Use of the copyright notice is the responsibility of the copyright owner and does not require advance permission from, or registration with the Copyright Office."
"... in the event that a work is infringed, if a proper notice of copyright appears on the published copy or copies to which a defendant in a copyright infringement suit had access, then no weight shall be given to such a defendant's defense based on innocent infringement."
In the US, you do not need to apply to the Copyright Office to be granted the copyright. You get it implicitly when the work is "fixed in a tangible medium of expression".
you do not need to apply for a copyright. you apply for papers to make lawsuits easier. they provide you with documented and notarized dates and actions.
And more worthwhile. Having a registered copyright allows you to potentially collect punitive damages with a successful lawsuit rather than just the actual market value of the usage.
Comments
Well first off, if you don't have a copyright (which it doesn't sound like you do) - no, there's no purpose. A copyright is actual legal material which you have to apply for, just like a patent (http://www.copyright.gov/forms/). However whether this is worth it or not depends on the nature of what you're putting up online.
Now about the copyright symbol itself:
http://inventors.about.com/od/copyrights/a/CopyrightNotice.h...
"A copyright notice or copyright symbol is an identifier placed on copies of the work to inform the world of copyright ownership. While use of a copyright notice was once required as a condition of copyright protection, it is now optional. Use of the copyright notice is the responsibility of the copyright owner and does not require advance permission from, or registration with the Copyright Office."
"... in the event that a work is infringed, if a proper notice of copyright appears on the published copy or copies to which a defendant in a copyright infringement suit had access, then no weight shall be given to such a defendant's defense based on innocent infringement."
In the US, you do not need to apply to the Copyright Office to be granted the copyright. You get it implicitly when the work is "fixed in a tangible medium of expression".
The quote in your last paragraph is the answer to the OP's question.
you do not need to apply for a copyright. you apply for papers to make lawsuits easier. they provide you with documented and notarized dates and actions.
And more worthwhile. Having a registered copyright allows you to potentially collect punitive damages with a successful lawsuit rather than just the actual market value of the usage.