If a work is available online then can’t anyone use it? Isn’t it public domain?

Copyright applies irrespective of whether the work is online. The work still has an author and copyright law still allows the author to set some rules on how their work is used by others. If not expressed somewhere in the online work itself, these rules will usually be found on the website’s copyright or terms of use webpages. Remember that works you find online may not have been put there by the creator.

A work falls into the public domain once copyright expires, which is 50 years after the death of the author in New Zealand. While many works available online are publicly accessible they are not likely to be in the public domain.