The following list outlines the number formats available in the number group on the Start tab. To see all available number formats, click the dialog Box Launcher next to numbers.
General: The default number format that Excel applies when you type a number. In most cases, numbers in the "General" format are displayed in the form of a type. However, if the cell is not wide enough to display the entire number, the general format rounds the number with a decimal point. The General number format also uses scientific count (exponential) notation for larger numbers (12-bit or more).
Currency: Used for general currency values and displays the default currency symbol with numbers. You can specify the number of decimal places to use, whether to use the thousand separator, and how to display negative numbers.
Numeric: A general representation of numbers. You can specify the number of decimal places to use, whether to use the thousand separator, and how to display negative numbers.
Accounting Private: It is also used for currency values, but it aligns the decimal point of the currency symbol and number in a column.
Time/Date: Displays the date and time serial number as a time value based on the type and locale (country/region) that you specify. The time format that begins with an asterisk (*) is affected by changes in the range date and time settings specified in Control Panel. Formatting without an asterisk is not affected by the control Panel settings.
Score: Displays a number as a fraction, depending on the type of score you specify.
Percent: Multiplies the cell value by 100 and displays the result with a percent sign (%). You can specify the number of decimal places to use.
Text: Treats the contents of a cell as text and displays the content exactly as you type, even if you type a number.
Special: Displays the number as a ZIP code, phone number, or social security number.
Scientific notation: Display numbers in exponential notation, replacing part of a number with e+n, with a number of n times 10, multiplied by E (representing the exponent). For example, the "scientific notation" format for 2 decimal places displays 12345678901 as 1.23E+10, that is, 1.23 times 10 of the power of 10. You can specify the number of decimal places to use.
Customization: Allows you to modify the copy of an existing number format code. Use this format to create a custom number format and add it to the list of number format codes.