It's easy to accidentally change the screen size of items your computer displays or of the resolution of the monitor itself, but this can be fixed just as fast. Your monitor's resolution is the number of pixels it is showing at one time; typically the greater number of pixels, the sharper the image. Resolution is adjusted from your computer's Display options. For windows, such as your Web browser or a folder you open, adjustments to make it full size are done in that window itself.
Change Monitor Resolution
Windows 8 will automatically choose what it thinks is best for your PC monitor, but you can adjust your screen to any supported resolution. To change your monitor's display, swipe in from the right edge of your screen and tap on "Settings" then "Change PC Settings." If you're using a mouse, hover over the lower-right corner of your screen and then click the two buttons in the menu that pops up. In the "Display" menu option, use the slider to adjust your screen's resolution. Microsoft recommends that you use the highest resolution your monitor can support.
Double-click the title bar of any window, whether it's a file window or Web browser window, to maximize it so that it will take up your whole screen. This action also brings it to the forefront of your screen. You can achieve the same effect by clicking the Maximize button, which looks like a square, in the upper-right corner of your window. Another way to maximize any window in Microsoft Windows is to hold down the Windows key press the Up arrow key. Repeating any of these methods twice will return the window to its previous size.
Full Screen Mode
Your windows and Web browser also have a full screen mode that will cause the page or video to take up the entire screen, even hiding your Windows menus, Charms bar and other buttons. Windows allows you to turn this on with the F11 key. Many Web browsers, such as Internet Explorer, Google Chrome and Mozilla Firefox also support using the F11 key to go full screen. To turn off this full screen function, simply press F11 again. On computers with compact keyboards, such as laptops, you may need to press fn-F11.
What Windows Saves
When you open a folder or program and adjust its size, Windows 8 will remember the size and position changes you make. Windows will display the folder or program in the same location and size when you next open it. Changes you make will only impact the program you're working with, so moving a Word document to the left-hand side of your screen won't change where an Excel sheet opens.