What is

Hi alanb1291,

Welcome to Web2.0calc forum.  we hope you like it here.

Thanks for that answer.  i just want  to clarify a couple of things.

 "Log10 of 100 is 2".  

This is worded log of 100 base 10 is 2   It is written   $$log_{10}100=2$$

This is true because $$10^2=100$$

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I have writen this in Latex - using the latex tab in the ribbon above 

$$log_{10}100=2$$    is written in as log_{2}100=2

and

$$10^2=100$$    is written in as 10^2=100

Why don't you have a play with it!

You can also get subscripts and superscripts to display via the drop down format keys in the top line.

does that make sense?

Its the power you need to raise 10 to to get the number. 

For example, Log10 of 100 is 2. That means you have to raise 10 to the power of 2 (in other words, square it) to get 100. 

Or the Log10 of 1000 is 3. So you have to raise 10 to the power of 3 (cube it) to get 1000. 

and the Log10 of 10 is 1. 

Obviously, the Log10 of most other numbers are not so tidy. 

So, your turn. What's the Log10 of a million? - that's it, 6