The concept of a sitemap isn’t actually close to being a new thing. But, until this past decade, this was a concept that only really sat upon the concerns of anyone but IT people and web designers. Companies had no need to worry about these, software developers had no reason to worry about these, and even passing users only partially had to worry about what it was, either. What They Are: A sitemap is basically a list of different pages, directories and constant files that make up a website. These can exist in various forms, such as formatted XML or document types that crawlers and search engines can document and properly index. It can also be a guidance document (an actual page itself), which users can look at, in order to know what’s where. It’s not unlike mall or airport directories that show you where different related things are, and give you a good sense of navigation that saves you endless wandering. What Changed: Well, there is an increasing migration of everything practical, to the internet. Since the website-oriented frameworks of SQL, PHP/ASP, HTML/HTML5 and so on are already there, and now quite advanced … well, use the framework that’s been worked out and is easily accessible to any device, right? Well, this means that everyone has to worry about site maps at least for the ability of search engines to better index you, for your internal search systems to properly find what people ask, and so on. Problem: The problem is that some standardization of web design, along with advanced, dynamic interactive interfaces for them, and of course that internal site searching concept, has made people less adherent to the practice of making site maps that can help users learn to navigate. Notice the prominence of having to click and wander, to figure out where anything is in modern web designs? This is because nobody makes site maps in the sense of directories for users to find their ways by. Even big websites like Twitter, YouTube and the like are reticent to actually be remotely helpful these days. Other Uses: Other uses of this concept are for design prototyping. When working out an SaaS or website design, mapping out where what goes is very important. First, work out the base layout concept, the navigation flows and so on, and then immediately begin mapping the site, so you know what pages need to exist, and what variations on the UX themes need to be made in order to support the differences across the board. You’ll spot problems where they exist, like miscategorization, way too many departments, or just a tangled layout with this kind of mapping process, and address them before users have time to even experience and complain about them. So, here is probably the biggest use these days, and probably the context that sent you looking this up. There’s of course a set of tech standards for sitemap designs used for engines and indexing systems, but that’s not our department here. When it comes to mapping for prototyping or for user reference … just use common sense. There are no best practices for that, and for once, we need to be glad there aren’t.