Sometimes people mistake me or others in my profession as the Copyright Police. And while it's true that we librarians may literally be the only people who care so passionately about adhering to copyright laws, I think most people out there - from teachers assembling a PowerPoint for a science lesson to students creating an infographic to instructional leaders presenting at conferences to bloggers who write for a living - they really do have some level of respect for intellectual property. Sometimes people get nervous with image use because they aren't sure if they really can use that image that they want to use, or if they go ahead and use it, they fret over whether they've cited it properly.
My advice is simple, and it's the same regardless of your age, purpose, or profession. If you want to be absolutely certain that you aren't breaking any copyright rules with images, then you have two choices:
1. Generate your own images, with your phone/camera/computer/tablet/whatever,
2. Use an Open Source or Creative Commons image.
Here are five - of MANY - websites that offer searchable collections of free, Open Source (free to use) images:
The great thing about these is that they provide pretty nice quality images - some clip art, but most are actual pictures, and you may have to wade through a few ads or sponsored images (ahem, Shutterstock) they're still providing you with gobs of content and asking nothing in return, not even account creation. And even though they don't require you to cite under most Creative Commons licenses, in my librarian heart of hearts I'll always do it anyway, even if just to promote their website. It's the least we could do, right?
What are your favorite sources for free, Open Source images?