Logarithm is the inverse algorithm of multiplication and square root discovered by Scottish mathematician Napier in astronomical research. This great invention delighted many mathematical researchers because it solved a big arithmetic problem. Logarithms are in the form of log and ln. The subscript of the form is a multiplier, the superscript is a final number, and the equivalent number is a power number. In our view, this is only a very simple mathematical calculation, but its appearance can bring shock and joy to people from all walks of life at that time, which shows its great significance. In fact, the essence of logarithm is directly related to the basic arithmetic multiplication and square root, which are three forms of arithmetic. Therefore, to understand the meaning of logarithm, we need to start with the analysis of the relationship between these three forms.

1, logarithm simplifies the handwriting process of multiplication. At first, we all wrote arithmetic multiplication one by one, such as 5*5*5. If it's short, you won't be too lazy to write, and there won't be a situation of missing and writing more, but these problems will appear when we accumulate more and more. Therefore, integrating a series of long arithmetic into a formula can reduce the amount of writing and improve the accuracy. Using power, it can be written as 5 3, and its equivalent value is 125, written in logarithmic form.

2. Logarithms can also be displayed on the image. Multiplication 5*5*5 can only represent a calculation, and 5 3 is just an expression. Changing any value can not only change the result, but also be an expression in essence. When it is converted into logarithm, it can draw an image in a plane rectangular coordinate system and become a curve with mathematical significance, which may be the reason why Napier is ecstatic.

3. Logarithm saves labor and prolongs the life of astronomers. This is Laplace's evaluation of Napier's logarithm. For astronomers and experts in other fields, the discovery of logarithm makes them not write a number with numbers, but with an expression, and it is supported by images.