Actually, it is more like 10,000 advanced calculators. Each cell is like a calculator, because it can contain numbers or formulae. So each cell can perform calculations on numbers in other cells. 

In order to perform multiple calculations on a calculator, they must be in order. You can think of a spreadsheet as having an extra piece of intelligence. It does not matter where or in what order the functions are. For example, a cell can do a calculation on data from cells that are hundreds of rows and columns away. The spreadsheet knows exactly where to go to get the information needed for a calculation. 

A spreadsheet is more advanced than a calculator since it can perform and keep track of many calculations at a time.