A structured reference is a special syntax for referencing Excel Tables. Structured references work like regular cell references in formulas, but they are easier to read and understand. Structured references are also dynamic, and adjust automatically when data is added or removed from an Excel Table.
Excel will enter structured references automatically when you reference parts of a table with point and click. This behavior is controlled by the preference "Use table names in formulas".
Examples
To get the total rows or columns in an Excel table:
=ROWS(table)
=COLUMNS(table)
To count or sum items in a column:
=SUM(table[amount]) // sum amount column
=COUNTA(table[item]) // count all in item column
To count visible rows in a filtered table:
=SUBTOTAL(3,table[Item]) // count visible in item column
Current row
Inside an Excel table, you'll see the following syntax for "current row":
=[@color] // current row in color column
Absolute references
References to single columns in a table are relative by default - when formulas are copied across columns, you'll see the column references change.
References to multiple columns are absolute and will not change when formulas are copied.
=table[@[amt]] // relative
=table[@[amt]:[amt]] // absolute