Three good rules to follow:
Copyright is a legal concept that protects the rights of authors/creators and their work from being used/copied without permission. It also protects the rights of those who want to use someone else’s work under the concept of Fair Use. In brief, you must have permission to use what belongs to someone else in certain circumstances, such as publishing.
Unlike using images in a paper that only your professor sees, when locating images for use in a digital project, you have to take into account that the general public will have access to the site. In order to respect copyright laws and the rights of creators, the general rule is that for any images published after 1923, you must get the copyright holder's permission. However, if the author has released their work under a license, such as a Creative Commons license, then there is more flexibility in using images for digital projects.
Essentially, Creative Commons (CC) licenses are a way to license copyrighted works, meaning that the author is giving permission to use their work in certain ways. There are CC licenses that put a work in the public domain, and some that say you just have to cite the author, and others that say you can remix and remake, as well as determine if you can make money off of their work. The most common CC license is CC-BY, meaning that if you use the material, you have to give credit to the original author. A full list of licenses is available on the Creative Commons website.
It's not enough to just find images that you have the rights to, but you also need to find images that are high enough quality that they will look good.
Never do a Google Image Search, click on an image, and then save the image or link to it that way. ALWAYS click View Image to get to the actual image, otherwise you may end up with a link that doesn't work, or an image that is too small.
A link to an image from a website has to end with one of the following to work properly:
If your link doesn't end with this, then the link has been set up to prevent people from downloading images from their website.
When doing a Google Image Search, you can click on Tools, then Size, then select Large to find images that will be of higher quality.
When creating something that is online, there are 2 options to add images to a website: adding a link to an image, or uploading an image. If you add a link to an image, you are usually taking a link you found via a search and copying and pasting the link; this is called hotlinking. This method has the advantage of letting users click on the image, and be taken to where the image was originally found, so the original creator of the image is connected to it. However, if the website takes down that image, you have a broken link, and it will no longer show up on your website. Hotlinking is generally frowned upon unless the creator of the media has given permission, and some websites are programmed to prevent this behavior. It is probably not a copyright violation, but it can be considered rude.
If you download an image from one site and upload it to your own, you have the advantage of making sure it stays up on your website; however, doing so implies that you have the right to use that image however you want. So if you are downloading images and uploading them to your own site, then you need to make sure that the image is either in the Public Domain (published on or before 1923), or you have permission from the image creator, or that there is an appropriate license (such as Creative Commons) that gives you the right to do so.