I want to know basic formulae of excel

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Microsoft Excel Shortcut keys
Enter data by using shortcut keysToPress

Complete a cell entryENTERCancel a cell entryESCRepeat the last actionF4 or CTRL+YStart a new line in the same cellALT+ENTERDelete the character to the left of the insertion point, or delete the selectionBACKSPACEDelete the character to the right of the insertion point, or delete the selectionDELETEDelete text to the end of the lineCTRL+DELETEMove one character up, down, left, or rightArrow keysMove to the beginning of the lineHOMEEdit a cell commentSHIFT+F2Create names from row and column labelsCTRL+SHIFT+F3Fill downCTRL+DFill to the rightCTRL+RFill the selected cell range with the current entryCTRL+ENTERComplete a cell entry and move down in the selectionENTERComplete a cell entry and move up in the selectionSHIFT+ENTERComplete a cell entry and move to the right in the selectionTABComplete a cell entry and move to the left in the selectionSHIFT+TABWork in cells or the formula bar by using shortcut keysToPressStart a formula= (EQUAL SIGN)Cancel an entry in the cell or formula barESCEdit the active cellF2Edit the active cell and then clear it, or delete the preceding character in the active cell as you edit the cell contentsBACKSPACEPaste a name into a formulaF3Define a nameCTRL+F3Calculate all sheets in all open workbooksF9 Calculate the active worksheetSHIFT+F9Insert the AutoSum formulaALT+= (EQUAL SIGN)Enter the dateCTRL+; (SEMICOLON)Enter the timeCTRL+SHIFT+: (COLON)Insert a hyperlinkCTRL+KComplete a cell entryENTERCopy the value from the cell above the active cell into the cell or the formula barCTRL+SHIFT+" (QUOTATION MARK)Alternate between displaying cell values and displaying cell formulasCTRL+` (SINGLE LEFT QUOTATION MARK)Copy a formula from the cell above the active cell into the cell or the formula barCTRL+' (APOSTROPHE)Enter a formula as an array formulaCTRL+SHIFT+ENTERDisplay the Formula Palette after you type a valid function name in a formulaCTRL+AInsert the argument names and parentheses for a function, after you type a valid function name in a formulaCTRL+SHIFT+ADisplay the AutoComplete listALT+DOWN ARROW

Auto sum shortcut key
Quickly create a Microsoft Excel formula to get the sum of all cells by highlighting the cells you wish to know the value of and pressing ALT and = .
Create hyper links in Excel
Quickly create hyper links in your Microsoft Word, Excel, or Front Page document by highlighting text and pressing "CTRL + K".
Close all open files at once
Close all open Microsoft Word and/or Excel files by holding down the shift key and clicking "File" and then "Close All".
Quickly open recently opened files
Quickly open the recent files by first pressing "ALT + F" to open the file Menu and press 1, 2, 3, or 4.
Create underlines without any text
This tip works with the majority of Microsoft Office applications. Easily create an underlined space by pressing CTRL + U to start the underline, then press SHIFT + Space for each underlined space you wish to create. An example of how this could be used is for printable forms, for example: Name: .
Print only sections of a document
Save on your printer ink by selectively printing in Windows programs such as Microsoft Word, Internet Explorer, WordPad, Outlook, etc. To do this highlight portions of text you wish to print and click print. In the printer dialog window under Page Range choose the option Selection. It is important to realize that not all programs or printer drivers support this feature.
Repeat recent action
Using the F4 key in Microsoft Office 2000 and above allows the user to repeat the last used action. For example, if you have changed the font of a selected text and wish to change another portion of text to the same font, pressing F4 will do this for you automatically.
Quickly undo
Quickly undo mistakes in the majority of most PC Windows program by pressing CTRL + Z.
Quickly above cell contents
In Microsoft Excel press CTRL + SHIFT + " to copy the above cells contents.
Using the Microsoft Excel Auto filter
Organize cells quickly by using Microsoft Auto filter. Columns that contains long listing of data can be easily sorted by using the Auto filter option, to use this option select the top rows of the columns you want to be used and select Data / Filter and Auto Filter. Once successfully completed you can use drop down arrows to filter the data automatically.