<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Relevant discussion may be found on the talk page . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (July 2013) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Relevant discussion may be found on the talk page . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (July 2013) (Learn how and when to remove this template message) </Td> </Tr> <P> The significant figures of a number are digits that carry meaning contributing to its measurement resolution . This includes all digits except: </P> <Ul> <Li> All leading zeros; </Li> <Li> Trailing zeros when they are merely placeholders to indicate the scale of the number (exact rules are explained at identifying significant figures); and </Li> <Li> Spurious digits introduced, for example, by calculations carried out to greater precision than that of the original data, or measurements reported to a greater precision than the equipment supports . </Li> </Ul>

What does it mean for a digit to be significant