I’ve been making some software and placing copyright symbol to them. The reason is to inform the public that my work is original and if want to use them they have to ask permission from me. One thing I learn of using the copyright symbol is from this article from this website. http://www.firstwriter.com/copyright/symbol.shtml
The first thing to note is that for copyright there is only one form of the symbol (©), unlike trade marks, where there is a symbol for registered trade marks (®) and a symbol for unregistered trade marks (™).
To qualify for use of the registered trade mark symbol (®) you must register your trade mark with the appropriate authority in your country, whereas the trade mark symbol (™) can be applied to any symbol you are using as a trade mark. Use of the copyright symbol is more similar to use of the trade mark symbol, as work does not need to be registered in order to use it.
You can place the copyright symbol on any original piece of work you have created. The normal format would be to include alongside the copyright symbol the year of first publication and the name of the copyright holder, however there are no particular legal requirements regarding this. While it has historically been a requirement in some jurisdictions to include a copyright notice on a work in order to be able to claim copyright over it, the Berne Convention does not allow such restrictions, and so any country signed up to the convention no longer has this requirement. However, in some jurisdictions failure to include such a notice can affect the damages you may be able to claim if anyone infringes your copyright.
A similar situation exists in relation to the phrase “All Rights Reserved”. This phrase was a requirement in order to claim international copyright protection in countries signed up to the 1910 Buenos Aires Convention. However, since all countries signed up to the Buenos Aires Convention are now also signed up to the Berne Convention (which grants automatic copyright) this phrase has become superfluous. The phrase continues to be used frequently but is unlikely to have any legal consequences.