Windows 8 will allow users to install apps which are not part of the Windows 8 store as well. However, if you are new to Windows 8, here are some instructions on how you can easily install and uninstall apps using the Windows 8 Store.
Installing Apps in Windows 8
To install an app on the Windows 8 store, you will need to move to the start screen by clicking on the Windows icon and then clicking on the Store tile. This will launch the Windows 8 store where you will be able to browse all the available apps and install them.
To install an app in Windows 8, click on the Install button and Windows 8 will download the app from the store and install it on your PC or tablet.
Uninstalling Windows Store Apps on Windows 8
When you install apps through the Windows Store, you will not be able to uninstall them through the regular “Add/Remove Program” option. The Windows 8 Add/Remove Program option only lists the applications you installed directly on your PC.
In order to uninstall an app that you installed from the Windows 8 store, head over to the “Start screen” by pressing the Windows Key. Now “Right Click” on the app you want to uninstall. After you do this, a menu bar will appear at the bottom of the screen using which you can uninstall the app from Windows 8.
Bonus Hint: If you have unpinned the app from the start menu, you can hit the Windows key and then start searching the name of the app (See: How to Search in Windows 8). Once you see the app in the search results, just right click on it and uninstall it using the menu bar displayed on the bottom.