Editing Scientific notation (section)

=== Estimated final digits ===
It is customary in scientific measurement to record all the definitely known digits from the measurement and to estimate at least one additional digit if there is any information at all available on its value. The resulting number contains more information than it would without the extra digit, which may be considered a significant digit because it conveys some information leading to greater precision in measurements and in aggregations of measurements (adding them or multiplying them together).

Additional information about precision can be conveyed through additional notation. It is often useful to know how exact the final digit or digits are. For instance, the accepted value of the mass of the [[proton]] can properly be expressed as {{val|1.67262192369E-27|(51)|u=kg}}, which is shorthand for {{val|1.67262192369E-27|0.00000000051|u=kg}}. However it is still unclear whether the error ({{val|5.1E-37}} in this case) is the maximum possible error, [[standard error]], or some other [[confidence interval]].