You can change default state of Num Lock key on Windows logon screen through registry.
Open Regedit.exe and navigate to HKEY_USERS\.Default\Control Panel\Keyboard
Find InitialKeyboardIndicators key. To enable Num Lock, set InitialKeyboardIndicators value to 2. To disable Num Lock, set InitialKeyboardIndicators value to 0.
Disabling Num Lock on login screen can come in handy if you are using a netbook where due to keyboard layout you need to manually disable Num Lock every time before typing in login credentials.
If you need to change computer name in OS X, follow these simple steps:
1) Open System Preferences
2) Go to Sharing
3) Change computer name in the box shown on screenshot below
There are several useful keyboard shortcuts for taking screenshots on a Mac.
Command + Shift + 3 – takes a screenshot of the entire screen and saves it as a file on your desktop.
Command + Shift + 4 – turns the cursor into crosshairs, with which you can select an area of the screen to capture. Captured image is saved as a file on your desktop.
Command + Shift + 4 and then press Space – turns the cursor into camera icon, with which you can select to take an image of the current window, the menu bar or the Dock. Captured image is saved as a file on your desktop.
If you want to save the captured image to the clipboard instead of directly to a file on your desktop, add Control key to the combination. So you would press Command + Control + Shift + 3 and Command + Control + Shift + 4.
Another way of taking screenshots is to use built in Grab application. It allows you to capture section of the screen, specific window or an entire screen. It also has a timer functionality, which captures the screen ten seconds after the timer has been started.
Some of you may have experienced App Store on your iPhone/iPod/iPad being very slow. The reason for this is Genius for Apps system service. After its turned off, you’ll see a noticeable improvement in App Store.
To turn off Genius for Apps follow these steps:
1) Open Settings
2) Go to Privacy
3) Go to Location Services
4) Scroll to the very bottom of the page and go to System Services
5) Set the status of Genius for Apps to Off.
This only works in iOS 6.