Can someone give me some examples of returning values?

Returning a value is basically the opposite of passing arguments to a function. It allows the function to give back data to whatever called it. Take this addition script, for instance:

local function doAddition(addend1, addend2)
    local sum = addend1 + addend2 -- add the values
end

As you can see, the above is a perfectly functioning addition method. However, it is of little use if there's no way to get back the sum. That's what returning is for:

local function doAddition(addend1, addend2)
    local sum = addend1 + addend2 -- add the values
    return sum
end

Perfect. The last thing that needs to be done is to provide a container to store the returned sum:

local function doAddition(addend1, addend2)
    local sum = addend1 + addend2 -- add the values
    return sum
end

local someInteger = doAddition(5, 5)
print(someInteger)

First, the above script defines the doAddition() function. Then, the variable someInteger is created, and it calls doAddition(), passing 5 and 5 as arguments. Within the function, the local variable sum is defined and is set to equal to addends one and two. Then, it passes back the value of sum. At this point, 10 should appear in your output.