In many cases, permission to download material from a website is given on the site itself, but the fact that material is available to be viewed on a website, or is accessible using P2P software or networks over the internet does not, by itself, mean that you can use it as you wish.
Do not assume that material you come across whilst online has been uploaded with the copyright owner’s permission: if the material is an infringing copy, or the person hosting the site was not in a position to give a permission on behalf of the copyright owner, you risk infringing copyright if for example, you download or copy that material.
Is everything on the Internet in the “public domain”?
The term “public domain” is used in a couple of different ways: (i) for material in which all copyright has expired, and (ii) for material, such as software, where the copyright owner gives very broad permissions to people to use it freely. The fact that something is on the internet does not mean that it is “copyright-free” or “in the public domain” in either of these senses.
Reference: Australian Copyright Council. Information Sheet G056v09 Internet: Copying & Downloading. Retrieved from http:// http://www.copyright.org.au/