V stands for vertical and used for look up specific function located in excels database.
column number - it is known as the Col_index_num - of the data you seek
function look for Lookup _value in the first column of the data table
VLOOKUP then locates and returns the information seek from another field of the same record using the supplied column number
It's most useful function Vlookup is a excel function we are already know how to sum ,average etc
It's database functionHere simple example
Usually lists like this have some sort of unique identifier for each item in the list
Vlookup function work on database,the list must have column be contain unique identifier KEY or ID