Does pivot column include all entries within the column? This is a quick fundamentals question. (maybe not even one) In linear algebra, a pivot column is a column where a pivot is located on. Does pivot column include all entries within the column even if the pivot position is on the second row of the column? (simply, can an entry of a pivot column be an entry on top of its pivot position?)

Yes, a pivot column is the entire column that contains a pivot position, including those elements above the pivot. Since the pivot positions don't change between echelon form and reduced echelon form, it doesn't matter if the elements above the pivot are zero or non-zero when identifying pivot columns.