In excel, how to have some cell references in the formula not change when you extend the formula

Question

I have a formula in excel that refers to a few cells. When I extend this formula row-wise or col-wise, i see that these cell reference get updated which is fine.

Now, I have one of the formulas which does a vlookup form a table in a diff sheet. Now, when i extend this formula, i want only the local cell reference to update but the reference to the table in the other sheet on which i do a vlookup should remain constant. Is it possible to do this?

Answer 1

Append dollar sign ($) to target column/row numbers like A4 -> $A$4

Answer 2

Also, when you use formulas like vlookup that need ranges, you can (and generaly should) use Defined Names.