Help With String Manipulation?

Alright, When you do string.find You can find a certain string inside of a string

a = " A B C D E F G "
if a:find("A") then
print("It has an a in it :O")
end

But when I try this, It doesn't return true or false, It returns numbers. What do they mean? xD Here is an example:

b = "Testing 1234"
print(b:find(3))
--It then returns 11 11

--

c = "Hello World!"
print(c:find("Wor"))
--Returns 7 9

What are the numbers?

The range of indices of the string, notice that in your "Testing 1234" example, the string "3" goes from the 11th character to the 11th character. In the "Hello World!" example, "Wor" goes from the 7th to the 9th character.