Q. I want to add more memory to my MacBook Pro laptop before I upgrade from OS X 10.8 to OS X 10.9. How can I tell if it's possible to add more without opening up the computer?
A. In OS X 10.8, click on the Apple menu in the top left corner of the screen and select About This Mac at the top of the list. The small window that appears shows information about the computer, including the version of the operating system, the type of processor and the amount of memory (RAM) installed.
Click the More Info button in the box. A bigger window pops up with even more information about the Mac. Click the Memory tab in the box to see additional information, including the number of memory slots on the computer's motherboard and if both are in use with certain sizes of RAM modules.
To see Apple's instructions for installing more memory, and the maximum amount you can install in your model, click the Memory Upgrade Instructions link in the bottom corner of the box to visit the support area of the company's Web site. Companies that sell memory modules, like Crucial and Kingston, have guides on their sites that walk you through buying the right type of RAM for your particular computer model.
Resizing Tiles on the Windows 8 Start Screen
Q. Some apps I never use have really big squares on the Windows 8 Start screen. Can I make these smaller and increase the size of the squares for the apps I do use?
A. The Window 8 Start screen is made up of "tiles" (those colored squares) in larger rectangular and smaller square sizes, and you can switch sizes for many of them. You can also rearrange the order of the tiles into more useful positions on the screen and group apps into customized combinations.
To change a large tile to a smaller one, right-click to select it. A menu bar pops along the bottom of the screen. Click the Smaller icon to reduce the size of the selected tile. To make a small tile bigger, right-click to select it and then choose Larger from the menu. This same menu also has options for pinning and unpinning apps to the Start screen.
If you have a touch-screen computer, you can select a tile by putting your fingertip on it and dragging down on the screen slightly before tapping your size option from the menu. Some tiles are "live," meaning they update themselves automatically with new headlines or images. If you find this behavior distracting, select "Turn live tile off" from the bottom menu bar; you can always turn it back on the same way.
To rearrange the apps on the Start screen, select and drag the tiles with your mouse or fingertip into new locations. If you are moving a tile from one end of the Start screen to the other, drag the tile down to the bottom of the screen first to zoom out for a better view so you can move the tile more easily to its new location.
This article originally appeared in The New York Times.