Definition:Napierian Logarithm

Definition
The Napierian logarithms are a system of logarithms where:
 * $\log_{\text{Nap}} 10 \, 000 \, 000 = 0$
 * $\log_{\text{Nap}} 9 \, 999 \, 999 = 1$

Thus:
 * $\log_{\text{Nap}} 10^7 x y = \log_{\text{Nap}} x + \log_{\text{Nap}} y$

Also defined as
Many sources use the term Napierian logarithm for natural (base $e$) logarithms.

It is wise to make sure of which is meant when referring to them.