I have just been asked this question as a response to my post about photos on Flickr.
Found several photos that might be useful for me re research but unsure about copyright. How do you know if the photo can be used?
When an image is uploaded onto Flickr, the image owner has the ability to attach a license. The automatic default setting is 'all rights reserved' but some images will have a creative commons license which means that they are 'free' to use but may have certain conditions attached to their use.
If an image has an 'all rights reserved' license, then you will need permission to use the image. You can contact the image owner by email through Flickr but you will need to sign up for a Flickr account. If you are using an image using creative commons, then you will need to adhere to the terms of the license.
To find the information about the license of a Flickr image look to the right of the image, under the heading "Additional information".
NB: Image captured using Kwout.