Important: This website is now read only (except to admins) to comply with the UK Online Safety Act. Composr CMS is in the process of migrating to a new Constitutional governance model and Bazaar development model, with functionality of the old website (constructed by ocProducts Ltd, the prior copyright holder, a UK company) spread between GitLab and the new website (which has no connections to the UK).
Do we have to worry about copyright issues if we use Google images?
Google images contains both copyrighted and public domain images. Some will have watermarks or other means of protection, but even those images which seem to be completely clear of any protection may still be copyrighted and monitored across the web by a service like Pixsy.
Nobody is uploading this content to Google to be shared with the world, it's just returning results of images it knows about by crawling websites. A lot of those websites likely do not want their copyrighted images in the search results but have failed to protect them from search engines.
I do suspect a lot of websites are using images obtained from a Google search without any repercussions but it's better to be safe than sorry. There are plenty of sites offering free public domain content, pixabay for instance. This is a useful article, How to Check an Image's Copyright? 5 Ways to Do It - Pixsy
I've learned that the best practice for images on a website is to use only images that you've taken with a camera/video, yourself. If possible. That way, no copyright issues can arrise.