There are two main references used within Excel formulas, which are Relative and Absolute.
Excel uses relative references as the default cell reference. When a formula is copied or moved to another location, this type of cell reference changes.
Absolute references refer to a cell in a specific location. Its reference does not change if the formula is copied to another cell. You apply an absolute address to a formula using the F4 key. A dollar sign ($) signifies that an address is absolute.