Microsoft co-founder Bill Gates says the decision to use Ctrl+Alt+Del as the command for logging on to a PC was a mistake, but over the years the shortcut has achieved cult status in geek circles. Here are 10 more useful keyboard shortcuts worth knowing.

1. Close browser
Whether your boss walks up while you're on Facebook or your other half comes in the room while you're buying them a gift, close your browser instantly with this shortcut:
PC: Alt + F4
Mac: Apple key + Q

2. Show desktop
If you have lots of windows open on your computer and you want quick access to your desktop hit the following keys:
PC: Windows key + D
Mac: F11

3. Add a bookmark
Create a shortcut to your new favourite website by bookmarking the page with the following quick trick:
PC: Ctrl + D
Mac: Apple key + D

4. Delete forever
When you know you want to dump a file forever – instead of sending it to clog up the recycling bin first – tap the keys below:
PC: Shift + Delete

5. Change zoom level
Whether you're working on the web or in a word processing program, zoom in or out with this command:
PC: Ctrl + scroll mouse wheel, Ctrl + plus sign; Ctrl + minus sign
Mac: Apple key + plus sign; Apple key + minus sign

6. Reopen previous tab in browser
Have you ever accidentally closed the browser tab you were looking at and had to spend time backtracking to find it again? The shortcut below will restore that page to you almost instantly:
PC: Ctrl + Shift + T
Mac: Apple key + Z

7. Go to a previous location in browser
This clever shortcut lets you quickly go back to the webpage you were looking at before your current one:
PC: Alt + F4
Mac: Apple key + Q

8. Select the address bar
When you want to quickly type a new URL into your browser, the shortcut below will easily select the address bar for you, so you can start typing without moving your mouse:
PC: Ctrl + L, or F6
Mac: Apple key + L

9. Spelling/Grammar check
No more excuses: Perfect spelling and grammar is just one keystroke away:
PC or Mac: F7

10. Add "http://www" to your browser's address bar
The quickest route to your online destination? Just type in the name of the webpage you'd like to go to (for example, type "Google", then press the following keys to add the "http://www." to the beginning and ".com" to the end.
PC: Ctrl + Enter
Mac: Apple key + Enter
So, what are you waiting for? Start using those easy shortcuts on your PC or Mac
- See more at: http://www.9janinja.com/2013/10/tech-10-keyboard-shortcuts-you-probably.html

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