With the release of Microsoft's new Operating System (OS) called Windows 8 in October in 2012 Microsoft has changed some of the key parts of the graphical interface that also change how users interact and navigate with their computers that have this new OS.
With Windows 8 Microsoft made massive improvements to the OS as a whole as well as adding new ones, a large majority of the improvements are things in the background that make windows run more smoothly and lower the minimum computing power needed to run windows. The largest change though that users will notice is the new start menu. With this new design allows for much friendlier touch input support, which are mainly touch screens and digital pens. Don't fret though, you can still navigate and use Windows 8 using just a mouse and keyboard.
Below are a few videos that will help you get on the right track about how to navigate the new start menu and other basic things with Windows 8.
The first 2 videos will introduce you to the new start screen interface and how to navigate it using a mouse and keyboard. The 3rd video will show you how to navigate using just a touch screen (mainly for tablet users)
Windows 8 - Beginners Guide Part 1 - Start Screen & Charm Bar
Windows 8 - Beginners Guide Part 2 - Quick Access Menu