Earlier this month, members of the Windows 8 team posted back to back posts (here and here) to the Building Windows 8 Blog in which they described the ways in which previous Windows versions, dating back to Windows 95, handled application launching, mostly through the Start Menu but more recently, in Windows 7, via the taskbar as well. In Windows 8, of course, these facilities are being taken over by the Start screen. For this reason, the Start screen is widely considered a "Start menu replacement." But it is, of course, much more than that.
Speaking generally, one of the big user experience advantages Windows has always had over the Mac is this notion of "Start." It provides an obvious starting point for virtually any activity in Windows, including finding and launching applications, accessing the file system, configuring system settings in Control Panel, interacting with devices, and shutting down and rebooting the PC. In other OSes, these and other Start resources are found scattered around the system, and users need to be experienced before they know where to look for particular things.
In Windows 8, the Start screen replaces the Start menu and the taskbar, but also the notification area and clock (parts of the taskbar, really) and, conceptually at least, Windows Gadgets. Unlike the Start menu, but like the taskbar, its links to available applications (legacy Windows applications), apps (modern, Metro-style apps), control panels and other elements are always visible. Like Windows Gadgets, these elements, called live tiles, are also dynamic, and will animate and change according to the needs or design of the underlying app.
Once you understand what this UI replaces, and how it does so, using it becomes more obvious. You can arrange tiles as you wish, and configure them in different ways. Tiles representing modern apps can be made small and square or large and rectangular, usually, while those representing legacy applications will always be small because they have no dynamic information to impart. Tiles can be grouped together into logical sections, and those groups can be optionally named and moved around, creating a highly customized environment that is both attractive and useful.
Microsoft is careful to state that the Start screen is not "the Metro shell" in Windows 8, but I think it's fair to say that the Start screen is the most obvious visual representation of the new Windows shell, which is based on the new Windows runtime, or WinRT. In this sense, it visually replaces the old Windows desktop--which would encompass the Start button, taskbar, desktop and Explorer windows, or what we previously thought of as "the shell." The Start screen doesn't directly support file system browsing, of course, but why would it? Neither do simpler systems like iOS. In a modern OS, perhaps, the lack of shell-based file system browsing is arguably a sign of maturity, not a detriment, just as the ability to fix a car is no longer a requirement for owning such a vehicle.
The Start screen, alas, is also the source of much controversy. Some of this is a matter of timing. What makes the Start screen great is apps, and we just don't have anything interesting to show off today. What we do have is a collection of sample apps, literally written by college interns, which come with both positive and negative connotations. On the one hand, the very existence of these apps proves that it is easy to adopt the new WinRT-based programming paradigm, meaning that developers will be able to get up to speed quickly in the new environment. But on the other hand, most of these apps are painfully basic, and to many power users examining the Windows 8 Developer Preview, what they see are a combination of familiar "legacy" applications that are quite powerful--Microsoft Office, Photoshop, and so on--and new but simple utility-like Metro-style apps. And it's hard to see, now, that this gulf will be bridged, and that we'll soon have powerful, full-featured Metro-style apps as well.
In fact, without getting too far afield here, I need to point out that the Windows 8 user experience at Beta and then again at RTM will be dramatically different from what we see today. By Beta, Microsoft will have opened up the Windows Store for beta testers and we'll start seeing a representative selection of Metro-style apps, apps which will begin replacing our daily-use "legacy" applications. So the need to switch back and forth between the Metro future and the desktop past will diminish. For many Windows 8 users, it won't exist at all, especially once the OS is broadly available.
While Microsoft was evolving the Windows UI between Windows 95 and Windows 7, there were some visual differences in each version, but the usage paradigms were always the same. And users were immediately familiar with the new versions, since the Start button led to a Start menu and there was a taskbar, desktop, and other immediately recognizable elements.
In Windows 8, this familiarity is seemingly discarded, but only at first glance. Start using the new OS and you'll find that many things still work the same or at least similarly. For example, let's say you are using the desktop version of Microsoft Word and you want to launch Notepad. In Windows 7, the quickest way to do that is to tap the Start button on the keyboard and start typing the name of the application--notep or whatever--in Start menu search. In Windows 8, it works the same way: Just tap the Start button on the keyboard and start typing the name. This time, application search results appear in the new full screen view, but it's the same basic activity. In fact, the Windows 8 version is more powerful.
(If you're already on the Start screen, you can simply skip tapping the Windows key. Just starting typing and the new search experience pops up.)
The Windows 8 Start screen can be customized just as the old Start menu could, but far more easily and to more useful effect. (And with PC-to-PC sync, this Start screen layout can be replicated to all your PCs.) And the screen scales better to today's HDTV displays than does a pop-up menu with tiny textual items.
Microsoft has data about how people actually use the Start menu today in the real world, but the real takeaway is that the addition of application launching to the Windows 7 taskbar caused people to use the Start menu less. A lot less. And by taking that new, more visual approach to the logical extreme and making it a full screen experience in Windows 8, the company will likely do for app launching and other common Windows activities that it did previously for Office commands when it introduced the ribbon UI in Office 2007: It will make them more discoverable and thus more frequently used. This is a good thing.
Anyway, I know people are freaking out about the new Start screen. And I know that enthusiasts and developers are busy working on little system utilities that will bring back some "missing" Windows 7 or XP features. Don't bother with this stuff, please. The future is in front of us; all it needs is some useful apps to make it a reality. And that will happen well before Windows 8 ships. Remember, the current public build is just a developer preview. There's a lot more coming, and if you think about it, for an OS release, it makes sense that the most important coming changes are the apps that run on top of the OS and not the OS itself. Give it time. The new Windows 8 Start screen isn't just a good idea, it's a great interface that will make sense on phones, tablets, PCs of all stripes, and even servers. And before you know it, you'll forget all about that old-fashioned Start menu.
Seriously. You will.