There are a variety of reasons...
1) Ignorance of the copyright laws.
2) Copyright "Urban myths" (I can use X amount of a work w/o permission, If I don't charge for it it's ok, etc)
3) The belief that the internet is anonymous so I won't get caught
4) I gave the original author credit so I can do it
5) If there's no copyright notice it's free for me to use.
Materials on the internet are protected by copyright, just as their analog counterparts.
Copyrights are important for internet websites because it protects original work. Copyright laws ensure that only the originators and people that are given permission can copy or change the work.
If copyright law did not apply to the internet, it would be nearly impossible to monetize anything on it.
Some torrents are illegal on the internet due to copyright issues. Sharing files on the internet that are copyright protected without the copyright holder's express permission is illegal.
drm was used to stop people from buying copyright thing over the internet
Certain things on the Internet are copyright. This is because it is someone work/ creation and is therefore illegal to use this persons work with out acknowledgement of the creator. Anything which says copyright ( such as artists songs) are copyright.
An infringement of the original authors' copyright.
Unless otherwise specified, virtually everything you encounter on the internet is protected by copyright and cannot be copied, altered, or further distributed without permission of the copyright holder.
They won't; copyright has nothing to do with that.
Contact the copyright holder and request permission.
You can't read it on the internet because of copyright laws.
People are lazy and horrible typists. Good grammar is something some people ignore on the internet because they don't care.