Usually, yes. You are usually required to let people know the image is A) not yours, B) who the creator/photographer is and C) an indication that you are legally using the image.
These guidelines are usually found on the website that provides the public domain or creative commons image.
Ideally you should mention the title of the image, name of the photographer or creator and provide a link to the source either below the image or in a bibliography. Preferably below the image. Sometimes you are asked to mention which licence the image is released under, which is usually the case with creative commons images.
Some examples of citing a creative commons image:
I advise that you do some research into attributions/citations for images before using the, This information can be found over at WikiMedia Commons.
I also strongly suggest you read the terms of using the image that the photographer or creator has put in place, sometimes they may differ from the standard attribution practices. Not often, but it pays to be safe.
If you wish to reuse a copyright-protected image, you need permission from the copyright holder or an exemption in the law.
The images in Monopoly are copyright, which means you will need legal permission from the games copyright holders to publish the image.
To use a picture from the Internet in a school report, you should first ensure that the image is copyright-free or obtain permission from the original creator. Properly cite the image source below the picture in your report and include a list of references at the end of your report if required.
If you are altering someone else's image, you need their permission.
Facts which are not considered common knowledge should be cited, regardless of copyright. Wikipedia articles, for example, should still be cited.
To obtain a license to use an image with copyright protection, you need to contact the copyright holder or their authorized representative. You will need to negotiate the terms of the license, including the scope of use, duration, and any associated fees. Once an agreement is reached, you will typically need to sign a licensing agreement to formalize the arrangement.
It should be assumed that a work is covered by copyright, as works do not need to state it, it is applied automatically.
It is an image that has been put as copyright. This means others may not use this image without permission, or legal action can be taken.
I'm pretty sure you need to cite it, you need to write a bibliography crediting the author if you take notes from it.
To use others' copyrighted works, you need an exemption in the law (such as fair use) or permission from the copyright holder.
No. If an image is trademarked for anything, you need specific permission from the owner of the image in order to use it. No matter what you use the image for, the owner of the image can still sue you for copyright infringement (I've seen it happen).
For personal use yes, but if you want to reproduce it for other people to use or see outside your house you will need to get permission from the copyright owner and probably pay a fee,