I want to copy paste a journal by an ADMIN
just to clear up everything.Copyright Infringement
Copyright Infringement is what most people are referring to when most people scream "art theft" or "stealing" but of course "stealing" and infringement aren't the same thing.
Copyright is a bundle of five rights which are exclusive to the copyright owner. These rights include the right to reproduce, distribute, create derivative works based upon, preform and display the protected work.
The owner controls all of these functions, subject to certain limitations and exceptions built into the law.
For most people copyright infringement involves the posting of their work or the manipulation (or "blending" or "editing" or "rendering") of their work. In these cases your actual work has been taken and directly used in some fashion.
There are a bunch of different ways which an infringement can occur but there are also exceptions and other situations where infringement might not be occurring so it is really important that you recognize when actual infringement has occurred and that you know how to proceed to remedy the problem(hint: mob action and death threats is not part of the procedure)Plagiarism
Sometimes plagiarism and copyright infringement are the same thing; sometimes they are not.
A plagiarist is a person who poses as the originator or a work which they actually obtained from someone else; they claim to have come up with words they didn't really write, ideas they didn't think up, facts they didn't discover, etc, etc.
When you guys talks about people "stealing your ideas" you are talking about plagiarism.
Now copyright infringement and plagiarism aren't always the same thing. For the purpose of plagiarism the material "stolen" doesn't have to be protected by copyright and the plagiarist cannot be sued for copyright infringement if all that they take are unprotected ideas or facts or things which can be considered to be in the public domain.
If someone were to take and submit one of your original works to deviantART and claim it as their own work, that person would be considered to be a plagiarist as well as a copyright infringer.
If someone were to take and submit your original work but not claim it as their own they would simply be committing copyright infringement.
If that same person were to take and submit the Mona Lisa they would not be committing copyright infringement (because the Mona Lisa is in the public domain) but if they claimed that it was their own painting then they would be considered a plagiarist.Copying
Aside from plagiarism, which is essentially copying while taking credit, we have just plain old copying.
Just like with the comparison between copyright infringement and plagiarism, simple copying is not necessarily either of those and this is where things get really, really confusing.
Artists have been copying from each other since the dawn of time but copying isn't always plagiarism and it also doesn't necessarily equal copyright infringement either.
Copying usually becomes copyright infringement when the copying is "verbatim"; the entire work is copied and copied exactly. There is usually no doubt that infringement has happened when two works are essentially identical in every way.
If there has only been "substantial" copying involved, with the works being obviously similar but not exactly the same it can become harder to have a valid claim of infringement, even more when the works are only superficially similar.
The main problem with copying is that the underlying idea behind your work, lets say a wolf howling at the moon in a dark forest, isn't protected under copyright.
Your exact rendition of the idea is protected and copyrighted to you, but anyone anywhere is free to use that idea in their own work, and many will do so without ever seeing your work and it is entirely possible that the works could simply share superficial similarities by coincidence without any copying having occurred.
Try Googling "wolf howling at the moon" and check the image results to see the sort of superficial similarities I'm talking about.