Numbers can tell you about anything- 3 dogs, 6 cats, 15 marbles, and so on.
Let's say we're talking about money and we want to compare $2.02 and $0.22. Which is bigger?
The pennies are here $2.02 and $0.22. Same number of pennies.
The dimes are here $2.02 and $0.22. $0.22 has more dimes maybe it's bigger?
The dollars are here $2.02 and $0.22. $2.02 has more dollars. Dollars are bigger than dimes and pennies, so the number with the most dollars is the biggest number.
What we do is look at the digits on the left and see which one is bigger. 6.12 is bigger than 5.34 because 6 is bigger than 5.
Be careful! If we look at the digits on the left we have to make sure we're looking at the digits we want.
234.56 is bigger than 78.95. The 2 is smaller than the 7, but we shouldn't compare the 2 and 7 because they aren't in the same places. The 7 is how many tens we have. The 2 is how many hundreds we have.
The 78.90 doesn't have anything in the hundreds place, so it's kind of like 078.95. The 2 and the 0 are both in the hundreds place, so we can say 2 is bigger than 0. That means 234.56 is bigger than 78.95.