What does Logarithm of a number actually mean?

Problem:
What does Logarithm of a number actually mean?
Solution:
Today, while working on a Dataset, I came across a Kernel from Kaggle, where it is using Log(x) to handle Skewed Distribution of x. I was clueless. First, I asked myself what is log(x) and I went blank! So, what I understand is I need to brush up my basic Math Skills and thus here I am!
What is log(x)?
A logarithm is a power to which a number must be raised in order to produce some other number. 
Example:
10 * 10 = 100
We need to multiply 2 of 10s to get 100. So, Logarithm is 2. In words,the base-ten logarithm of 100 is 2 and we can write it as below:
log10(100) = 2
Here, we are dealing with three numbers:
  • the base: the number we are multiplying ( “10” in the example above)
  • how many times to use it in a multiplication (2 times, which is the logarithm)
  • The number we want to get ( “100”)

Another Example:

log2(8) = ?
Here, we are trying to answer, how many times we have to multiply the Base Number(here it is 2) to get the number we want(here it is 8).
 2 * 2 * 2 = 8
That means, 3 times.
So, log2(8) = 3
Thus, the logarithm tells us what the exponent is!
Common Logarithm: The logarithm has the number 10 as its base.
Natural Logarithm: This Logarithm has the number e (≈ 2.718) as its base.
Binary Logarithm: This Logarithm uses base 2.
Thank You!
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