As anyone who uses PhotoShop will be aware, images are not always what they seem!
Some images may be unintentionally misleading, sometimes there could be deliberate intent to deceive.
Look out for the clues that can help you assess them:
Source of the image
Information about the maker of the image
Reason for creating the image. Do you think there is any bias towards a particular viewpoint?
Use of colour - is there a message there?
Style of the image - e.g. nostalgic, larger than life
Is it an original image, or has it been altered?