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We have an array where we need to select a random value from that array.

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Currently, we have three different items within that array, three different text strings, and we

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possibly could have more.

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So we want to make this as dynamic as possible as well as we don't want the user to know which element

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and which string value we're going to be outputting.

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And this is where we turn to Amarth random.

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This is a function in JavaScript that returns a number in the range of zero to one inclusive of zero,

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but not of one.

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So basically you're going to get return back a value that's zero decimal and a whole string of numbers.

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And here's some examples of what happens and how the output looks within math.

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Random.

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So over here, we're just simply got a math random and this is a typical number that gets returned.

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So if we do want to have a random number, that's a particular value that we need to multiply that number

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by the value that we want to have output.

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There's an example here of how to get a random integer.

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So minimum, maximum.

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So we've got minimum is the math seeling.

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Maximum is the math flaw plus minimum.

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So essentially what we're doing is we're doing math for multiplying it by math, random, and that's

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returning back the number.

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So let's go ahead and take a closer look at this within our ED.

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So going into play the game, first of all, let's create a random number.

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So we'll call it random number using math.

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I don't see what that's going to return, so a console log out the value of a random number, so refresh

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and every time we hit start, we get a random number.

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So it's got a lot of decimal.

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It's decimal with a lot of numbers.

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So we want to actually multiply that by a meaningful number.

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And if we want to have a number from zero to nine, we could multiply it by 10.

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So that would give us a random number, anywhere from zero to nine, and just to be sure, this is where

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we could do math, fluorosis, another builtin not function in JavaScript, and that would actually

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bring the returned value down to the floor to make sure that we're rounding it down to the nearest floor

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value.

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And as we saw over here, when we use floor, then this is the rounding a down to the nearest full number.

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Whereas if we do math ceiling, we're rounding up to the nearest full number.

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So that's what the difference there is.

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So right now, if we press it multiple times, you're going to see that we're always returning the number

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back anywhere from zero to nine.

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So there's nine.

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And if we keep going, we see that we've got a zero.

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So we never get 10.

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If we do want to have 10 that we can add plus one, this will return back a number from one to 10.

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And as you can see, 10 got returned back there.

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And if we want to get a random item from our array, we know that this is an array and arrays have length.

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So instead of 10, we could do wording Dorte length and this is going to be equivalent to three.

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I'm going to get rid of that zero one because arrays are zero based and we want to actually return a

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number back anywhere from zero to two.

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And as you can see, the numbers being returned back are always within that range, within a random

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number.

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You could try it out for yourself as well.

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So the next thing that we want to do is output within that message.

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So taking message and updating the inner text of message.

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We're going to use the wording, ouray.

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And specify an index value and that index value is going to be equivalent to that random value.

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So essentially, as we saw, we're getting a value of zero one or two because we have three items within

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the array.

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So that's indicated by that length index values from the array.

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And this is dynamically so in case our rate increases in length, our formula will always still work.

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So go ahead and try it out for yourself.

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That's not random and try some of the examples, generate some random numbers and output in the console.

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And coming up next, we'll show you how you can update the start button as well as how we can set a

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start time when the user presses the start button.

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And then another time that we can get when the user completes typing and hits the end button.

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So all of that is still yet to come.