Does it really happen in Excel?

False

In excel you can use the sum function to add up an entire column. In Excel, you can use the sum function to add up entire columns, rows, or individual cells as you please. It is not practical to do the calculations yourself unless you are checking your spreadsheet for accuracy. Itis most effective to allow excel to do the calculations with the sum function because if you edit any of the cells that are being used with the sum function, the total will be changed accordingly. (for example: 1 + 1 = 2. If you decide to change the first number to a 2, excel will calculate 2 + 1 and give you 3.)