A Caveat of Creative Common Licenses
If you want to use free illustrations on your website, there are many sites offering a broad selection of illustrations. You can choose from people, animals, objects, scenes and more in color or black and white. Web designers can literally spend hours browsing the various options to find one that exactly conveys their meaning. Unfortunately, free illustrations often come with catches. You have to read the site's terms carefully before using one of their illustrations.
Many free illustrations have Creative Commons licenses. There are many variations of the CC license; you must understand which one the illustration has before you use it. If you misuse a CC licensed illustration, you could be liable for copyright infringement and be sued.
CC Zero, or CC, is the most lenient license. You can do anything with the illustration, including using and altering them as a person sees fit, without attribution. If you see a BY after the CC, it means you have to give the creator of the illustration created. If you see a NC after the CC, it means you can't use the illustration for commercial purposes. If you see a NC after the CC, you can't change the illustration in any way. If you can't do any of these things, you will see the license listed as CC BY-NC-ND.
Sites offering free illustrations include Open Doodles and Pixeltrue Free Illustrations, where no attribution is required and you can use the illustrations for commercial use if you want. If you want Christmas illustrations, you can go to Merry Christmas illustrations, but attribution is required.
In many cases, you can't redistribute the illustrations on your own website or use them on mugs and T-shirts you sell. If you want to use free illustrations for these purposes, read the licensing requirements very carefully to avoid any problems. For more information click here https://www.reddit.com/r/webdesign/comments/l656hm/whattolookoutforwhenusingfree_illustrations/.