I had a question on another post on how to convert Nov 21, 2014 into a date Excel recognises. The solution involves six functions working together.
I was looking at a calendar and noticed it used alternately shaded cells, like a checkerboard, for all the dates and thought Excel could do that.
Sometimes data that comes into Excel with code numbers formatted as text. This can stop VLOOKUP functions from working and return the dreaded #N/A error. With a couple of tweaks you can lookup both real numbers and text numbers in the one formula.
The WEEKDAY function allows you to convert all dates into a number from 1 to 7 representing their weekday, from Monday to Sunday.