All the credits
The airport directory lives from cooperation and contribution. This page is dedicated to giving credit to everybody who is somehow (wittingly or unwittingly) contributing to this project. Thanks!
About >90% of the airport information on display is derived from one of the last public NGA DAFIF copies.
Please note that the DAFIF is no longer publicly available.
The Airport Detail-Page displays some weather information which is derived by PHP Weather from the NOAA.
Since a significant amount of traffic comes from searches for "weather icon" and related searches like "rainy" and "sunny" combined with "icon", here some info on this:
As you can see above, I use Custom Icon Designs's Weather Icons. They are perfect for my needs: They look good, they're free for non-commercial use, they come as transparent PNGs and in many sizes.
However, some people may not be satisfied with a set of "only" 16 icons. If so, I would recommend to take a look at the Wikimedia Commons MeteoSet Icons. Although they dont look as good as the CID-ones, they can be combined easily to match the exact METAR terminology. Professional developers will happily note that they're created in SVG, which means they can be combined on a code level rather than having to employ complicated graphics modules.
If these do also not match your needs, maybe check out the Wikimedia Commons Category for Weather Icons, there is some useful stuff in there as well. I especially like the Tango Projects Weather Icons, they look nicer but are less combinable than the Meteoset Icons. However, since its SVGs this can also be accomplished.
The Maps and the Runway views are - obviously - provided by Google. Say all you want - I love their products.
The imagery on the images pages are derived from the Google Panoramio, Google Picasa and Yahoo Flickr Web APIs.
The Airport/Airline Route information is derived from the Airline Route Mapper tool. In case of any questions, please turn to its owner, "cockpitvisit" using this flyertalk forums thread