How-To Geek on MSNOpinion

You need to know what the double unary operator (--) does in Excel

It's marginally more efficient: While the difference is negligible, the double-unary operator can be more efficient in ...
How-To Geek on MSN

You need to know the difference between a range and an array in Excel

Excel processes the range (A1:A10) by converting it into an array in memory. This array is what Excel works with to calculate the sum. The distinction is subtle but important: while the range is the ...