Reliability and accuracy.. whats the difference?

Please help

Accuracy is a measure of how close to the actual value your reading is. For example, if I have a 5mL pipette, and I set it to 5mL but it dispenses only 4mL, that is not accurate.

Precision is a measure of how reliable your values are. Using the pipette example again, if the pipette dispenses 4mL, then 4mL again, then 4mL again and 4mL again, it's highly precise (or reliable), but not accurate.

If it were to dispense 4.9mL, 5mL, 4.8mL and 5.1mL, it would be fairly accurate, but not precise.

Does that help?

The question is not about precision and accuracy.

Accuracy is altering the apparatus and reliability is altering the readings.

What? Accuracy and reliability are measurable things, not changing things.