Value member and Display member

Question

Sir, I need your help in the following topic.

I am often confused of value member and display member in comboBox fill funtion.

I have no doubt on filling a  non- dependent table.

but in the case of a foreign key column, I am became confused.

let me know which column should be set as Valuemember and Displaymember?

I have a knowledge that primary key to be set as Display and the column we want in
combobox to be set as Valuemember. Is this correct?