In the "old days" of web development, you had separate files for each page on your website which contained a variety of information -- the design of the site, a menu system, as well as the content of the particular page. As the web has evolved, we've begun to try to keep some of these things separate (you may have heard discussions about separating presentation and content). Since most sites are now driven by some kind of a database, the content of each page doesn't have to be kept in a separate file.
Starting today, our default web design projects will include a slide down warning for users of Internet Explorer 6 or earlier. It doesn't prevent access to the page, but simply explains that the browser is outdated, insecure, slow, displays content incorrectly and doesn't abide by web standards. It gives a handful of other options for the visitor to explore: Firefox, an updated version of Internet Explorer, Safari, Chrome, and Opera. (Websites such as Facebook, Youtube and Gmail have been doing this for some time now).
When people share links to your site on their Facebook profiles, Facebook will try to scrape your page to find appropriate content and imagery to attach to the link. If it can't find the correct information, it will sometimes attach unrelated images to the link. If you want to better control your non-profit brand, you may want to manage what Facebook pulls in to shared links.