What is the use of excel's nesting function?

devision

Well Irfan the use of nesting functions depends on what result do you want actually by nesting different types of funtiones. 

For example you are looking to use an "IF" function to return a value comparing between figures which are already calculated with the help of different functions, lets say AVERAGE and SUM you nest both the functions to get a desired result.

The following formula uses a nested AVERAGE function and compares the result with the value50.

=IF(AVERAGE(F1:F5)>50,SUM(G1:G5),0)

Here the formaula is saying that if the Average of all the figures in Cell F1 to F5 is greater then50 the return the value of the SUM of the values in Cell G1 to G5, otherwise, return with0. 

When a nested function is used as an argument, it must return the same type of value that the argument uses. For example, if the argument returns a TRUE or FALSE value, then the nested function must return a TRUE or FALSE.

I hope this helps.