1. Images that are copyright and which you cannot license for use.

Most of the images on this site are copyright and cannot be re-used without the express written permission of the copyright holder. For practical purposes copyright of images is owned by the site webmaster and permission should be sought before you copy, distribute and/or modify any image.

2.Images that are in the public domain and which require no license.

Some of the images on this site are in the public domain. These are clearly marked with a grey copyright symbol with a diagonal line through. The original copyright owner(s) of these images have put the image into the public domain for any use that you see fit. There are no restrictions on how they might be used.

3. GNU Free Documentation License.

In brief:
The GNU Free Documentation License is a form of copyleft (as opposed to copyright) intended for use on a manual, textbook or other document to assure everyone the effective freedom to copy and redistribute it, with or without modifications, either commercially or noncommercially. Any image used on this site under the GNU Free Documentation License will clearly show a GNU license link thus


To use an image, you must read the full license [here]

4. Creative Commons Attribution ShareAlike License.

In brief:
You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). Any image used on this site under the Creative Commons Attribution ShareAlike License will clearly show a CC license link thus


To use an image, you must read the full license [here]