F1

• Almost always used as the help key, almost every program will open the help screen when this key is pressed.
• Enter CMOS Setup.
• Windows Key + F1 would open the Microsoft Windows help and support center.
• Open the Task Pane.

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F2

• In Windows commonly used to rename a highlighted icon or file.
• Alt + Ctrl + F2 opens document window in Microsoft Word.
• Ctrl + F2 displays the print preview window in Microsoft Word.
• Enter CMOS Setup.
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F3

• Often opens a search feature for many programs including Microsoft Windows.
• In MS-DOS or Windows command line F3 will repeat the last command.
• Shift + F3 will change the text in Microsoft Word from upper to lower case or a capital letter at the beginning of every word.

F4

• Open find window.
• Repeat the last action performed (Word 2000+)
• Alt + F4 will close the program currently active in Microsoft Windows.
• Ctrl + F4 will close the open window within the current active window in Microsoft Windows.

F5

• In all modern Internet browsers pressing F5 will refresh or reload the page or document window.
• Open the find, replace, and go to window in Microsoft Word.
• Starts a slideshow in PowerPoint.

F6

• Move the cursor to the Address bar in Internet Explorer and Mozilla Firefox.
• Ctrl + Shift + F6 opens to another open Microsoft Word document.

F7

• Commonly used to spell check and grammar check a document in Microsoft programs such as Microsoft Word, Outlook, etc.
• Shift + F7 runs a Thesaurus check on the word highlighted.
• Turns on Caret browsing in Mozilla Firefox.

F8

• Function key used to enter the Windows startup menu, commonly used to access Windows Safe Mode.

F9

• Opens the Measurements toolbar in Quark 5.0.

F10

• In Microsoft Windows activates the menu bar of an open application.
• Shift + F10 is the same as right-clicking on a highlighted icon, file, or Internet link.
• Access the hidden recovery partition on HP and Sony computers.
• Enter CMOS Setup.

F11

• Full-screen mode in all modern Internet browsers.
• Ctrl + F11 as computer is starting to access the hidden recovery partition on many Dell computers.
• Access the hidden recovery partition on eMachines, Gateway, and Lenovo computers.

F12

• Open the Save as window in Microsoft Word.
• Shift + F12 save the Microsoft Word document.
• Ctrl + Shift + F12 prints a document in Microsoft Word.
• Preview a page in Microsoft Expression Web
• Open Firebug.