A plain range of cells is fragile. A Table is the same data with built-in intelligence. If you only change one habit in Excel, make it this: press Ctrl + T on your data.
How to create one
Click any cell in your data and press Ctrl + T. Tick My table has headers and click OK. Your data now has banded rows, filter buttons and a Table Design tab on the ribbon.
1. It grows by itself
Type in the row below the table and the table expands. Formulas, charts, pivot tables and drop-downs that use the table include the new row automatically.
2. Formulas fill down on their own
Write a formula in a new column and Excel copies it to every row. No dragging.
3. Readable formulas
Instead of =SUM(C2:C500) you can write =SUM(Sales[Amount]). These are called structured references, and they never need updating when rows are added.
4. Easy filtering and sorting
Filter buttons are already there, and headers stay visible when you scroll, replacing the need to freeze panes in many cases.
5. A total row in one click
Tick Total Row on the Table Design tab and pick Sum, Average or Count for each column. It uses SUBTOTAL, so it respects your filters.
6. Slicers
Click Insert Slicer on the Table Design tab to filter with buttons. It looks great in reports and dashboards.
7. Pivot tables stay current
A pivot table built on a Table picks up new rows when you press Refresh.
Name your table
On the Table Design tab, change the name from Table1 to something meaningful such as Sales. It makes every formula easier to read.