The zero function gives you a zero point from which to start your weighing process. If you are using a heavier weighing pan (with an ErgoClip, for example) or perhaps have a protective mat on the weighing pan, the zero function effectively ignores this as any weight that is already recognized by the weighing cell is not included as part of your weighing process. However, any weight on the balance still contributes towards the maximum load you are able to place on the balance (i.e., the balance capacity). When using the tare function, the balance internally records the weight that is already on the weighing pan and resets the display to zero, ready for something further to be added to the balance. When the results are recorded electronically, they will be shown with T for tare weight, N for net weight, and G for gross weight.