Copyright

"Copyright" describes the rights given to creators for their literary and artistic works.
But we often don’t consider copyright when we look at our family photos, or go to get them copied. Even though it is so easy to copy an image—with scanners, photo-quality printers, and copy stations—it is still illegal.
Things to remember about copyright:
Copyright is a property right.
Just because you buy a print does not mean you have purchased the copyright.
Professional photographers are the smallest of small copyright holders.
Under the Federal Copyright Act of 1976, photographs are protected by copyright from the moment of creation.
Photographers have the exclusive right to reproduce their photographs (right to control the making of copies).
Unless you have permission from the photographer, you can’t copy, distribute (no scanning and sending them to others), publicly display (no putting them online), or create derivative works from photographs.
A photographer can easily create over 20,000 separate pieces of intellectual property annually.
Professional photographers are dependent on their ability to control the reproduction of the photographs they create.
It affects their income and the livelihood of their families.
Even small levels of infringement—copying a photo without permission—can have a devastating impact on a photographer’s ability to make a living.
Copyright infringements—reproducing photos without permission—can result in civil and criminal penalties.
Put copyright in perspective:
65% of PPA photographers are self-employed photographers relying exclusively on photography as their primary source of income.
47% of member studios rely on reprints as a profitable source of income.
How to get legal copies of professional photographs:
Contact the photographer/copyright owner. Photographers are happy to discuss options for reproducing photos with you.
Check both the front and back of a print for a copyright notice. If it is a school, sports or similar type photo, you may want to contact the institution where the photo was made.
Contact PPA’s Service Center for help finding photographers to obtain photo-copying permission.
Use the Photographer Registry Web site to locate a photographer/copyright owner at www.PhotographerRegistry.com, so you can obtain reproductions or permission. With a few pieces of information about a photographer (i.e., they did portraits in Anytown, USA in 200X), a search can be conducted to find the copyright owner.
from Wikipedia via Copyright, Designs & Patent act of 1988:
Copyright can subsist in an original photograph, i.e. a recording of light or other radiation on any medium on which an image is produced or from which an image by any means be produced, and which is not part of a film.[12] Whilst photographs are classified as artistic works, the subsistence of copyright does not depend on artistic merit.[12] The owner of the copyright in the photograph is the photographer – the person who creates it,[13] by default.[14] However, where a photograph is taken by an employee in the course of employment, the first owner of the copyright is the employer, unless there is an agreement to the contrary.[15]
Copyright which subsists in a photograph protects not merely the photographer from direct copying of his work, but also from indirect copying to reproduce his work, where a substantial part of his work has been copied.
Copyright in a photograph lasts for 70 years from the end of the year in which the photographer dies.[16] A consequence of this lengthy period of existence of the copyright is that many family photographs which have no market value, but significant emotional value, remain subject to copyright, even when the original photographer cannot be traced (a problem known as copyright orphan), has given up photography, or died. In the absence of a licence, it will be an infringement of copyright in the photographs to copy them.[17] When someone dies the rights will have transferred to someone else, perhaps through testamentary deposition (a will) or by inheritance. If there was no will, or if the photographer has not specified where the rights in the material should go, then the normal rules of inheritance will apply.[18] Scanning old family photographs, without permission, to a digital file for personal use is prima facie an infringement of copyright.

Certain photographs may not be protected by copyright. Section 171(3) of the Copyright, Designs and Patents Act 1988 gives courts jurisdiction to refrain from enforcing the copyright which subsists in works on the grounds of public interest. For example, patent diagrams are held to be in the public domain, and are thus not subject to copyright.