There is often a temptation to use photos to brighten up a page without giving much thought to whether it helps serve a real purpose, or whether it might even be detrimental to the page. This article contains several useful tips about how to use the right photos, and what to avoid when using images on a webpage.
URLs (the technical name for web addresses) are highly important for computers as they uniquely identify every page on the web. The content of URLs is also hugely important for search engine rankings. But many users also find them a useful way to navigate a website.
Some useful tips on creating good URLs from a usability point of view. This is a very old article, but the advice still holds true.
Microsoft Research have conducted an eyetracking study of search engine use that found that people spend 24% of their gaze time looking at the URLs in the search results.