TODAY, YEAR, DAYS FUNCTIONS

TODAY( ):
I have given here about the formula syntax and usage of the TODAY function in Microsoft Excel.
 
Description:
Returns the serial number of the current date. The serial number is the date-time code used by Excel for date and time calculations. If the cell format was General before the function was entered, Excel changes the cell format to Date. If you want to view the serial number, you must change the cell format to General or Number.
 
The TODAY function is useful when you need to have the current date displayed on a worksheet, regardless of when you open the workbook. It is also useful for calculating intervals.

Note: If the TODAY function does not update the date when you expect it to, you might need to change the settings that control when the workbook or worksheet recalculates. On the File tab, click Options, and then in the Formulas category under Calculation options, make sure that Automatic is selected.
 
Syntax:
TODAY()
The TODAY function syntax has no arguments.
Note: Excel stores dates as sequential serial numbers so they can be used in calculations. By default, January 1, 1900 is serial number 1, and January 1, 2008 is serial number 39448 because it is 39,447 days after January 1, 1900.
 
Q:
How to use Today function to find the age of a person’s born in 1983?
Type the function as follows in the cell that you would like to get the result in:
=YEAR(TODAY())-1983
 
For more understanding, look at the screenshot please:

YEAR( ):
I have given here about the formula syntax and usage of the YEAR function in Microsoft Excel.
 
Description:
Returns the year corresponding to a date. The year is returned as an integer in the range 1900-9999.
 
Syntax:
YEAR(serial_number)
The YEAR function syntax has the following arguments:
Serial_number    Required. The date of the year you want to find. Dates should be entered by using the DATE function, or as results of other formulas or functions. For example, use DATE(2008,5,23) for the 23rd day of May, 2008. Problems can occur if dates are entered as text.
 
Remarks:
Microsoft Excel stores dates as sequential serial numbers so they can be used in calculations. By default, January 1, 1900 is serial number 1, and January 1, 2008 is serial number 39448 because it is 39,448 days after January 1, 1900.
 
Values returned by the YEAR, MONTH and DAY functions will be Gregorian values regardless of the display format for the supplied date value. For example, if the display format of the supplied date is Hijri, the returned values for the YEAR, MONTH and DAY functions will be values associated with the equivalent Gregorian date.
 
Q:
How to use Year function to copy the present year from your computer?
Type the function as follows in the cell that you would like to get the result in:
=YEAR(TODAY())
 
For more understanding, look at the screenshot please:

DAYS( ):
I have given here about the formula syntax and usage of the DAYS function in Microsoft Excel.

Description:
Returns the number of days between two dates.

Syntax:
DAYS(end_date, start_date)

The DAYS function syntax has the following arguments.
End_date    Required. Start_date and End_date are the two dates between which you want to know the number of days.
Start_date   Required. Start_date and End_date are the two dates between which you want to know the number of days.
 
Note: Excel stores dates as sequential serial numbers so that they can be used in calculations. By default, Jan 1, 1900 is serial number 1, and January 1, 2008 is serial number 39448 because it is 39447 days after January 1, 1900.
 
Remarks:
If both date arguments are numbers, DAYS uses EndDate–StartDate to calculate the number of days in between both dates. If either one of the date arguments is text, that argument is treated as DATEVALUE(date_text) and returns an integer date instead of a time component. If date arguments are numeric values that fall outside the range of valid dates, DAYS returns the #NUM! error value. If date arguments are strings that cannot be parsed as valid dates, DAYS returns the #VALUE! error value.
 
Q:
How to use days function to find the days that you have been living in this world since you born?
Type the function as follows in the cell that you would like to get the result in:
=DAYS(TODAY(), DATE(1983,01,01())

For more understanding, look at the screenshot please: