For me the math functions and totaling columns of numbers
The SUM function would be the most commonly used function in Excel.
The MODE function.
If by the top function, you mean the most commonly used one, that is probably the SUM function.
There is no step function in Excel. However, you can use excel to create a Step Function Chart. See related links for a video to explain the process.
Function
There are a number of functions in Excel that can manipulate time values. The TIME function and the TIMEVALUE function may be the ones that are most useful. It depends on what you want to be able to do, when you say "convert time".
In Excel Where are the various function categories stored on the Ribbon?
There is no function of that name in Excel. There is a function called VLOOKUP which stands for Vertical Lookup, and is probably what you mean.
functions of excel
The MODE function finds the most commonly occurring number in a range of numbers.
Syntax is very important when writing Excel formulas. Each formula and function will help guide you through how to format the equation. Probably the most important thing to remember about syntax is to begin all formulas with the equal sign, or Excel will just interpret your entry as text and not calculate anything.EXAMPLE: =SUM(A1:A12) [Adds the contents of cells A1 through A2]
A nested if.