Final answer:
The use of relative and absolute cell references in computer spreadsheets.
Step-by-step explanation:
In the context of computer spreadsheets, a relative reference is a cell reference that can change based on its location when it is copied or filled to other cells.
An absolute reference, on the other hand, does not change when it is copied or filled to other cells.
When a cell reference contains both a relative and an absolute reference, it means that the row or column is fixed while the other part can change based on the copied or filled cell.