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In this video we're going to move on to our next big subject which is type meditations and type inference.

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These are technically two different systems inside of typescript but we're going to talk about them

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in parallel for a very good reason just to make things a little bit more complicated as well.

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These two different features apply slightly differently to variable declarations functions and objects.

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So we're going to first talk about type annotations and inference as applied to variables.

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We'll take a break and talk about them applied to functions and then objects and so on.

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For each of these different subjects we're going to once again through go through some plain definition

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and overview.

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Well then take a look at some different code examples that we're gonna write out together.

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You'll notice I swap these two steps right here this time around.

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So we'll then talk about why we care about this annotation and inference stuff and we'll discuss when

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to use it.

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So let's get to it.

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First off some plain definitions.

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So type meditations.

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What is that.

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A type invitation is some tiny bit of code that you and I are going to write to tell typescript what

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type of value a variable refers to.

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All right.

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Now before expanding on that definition let's talk about what type inferences.

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So type inference type script is going to attempt to automatically figure out what type of value a variable

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refers to.

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And you'll notice that the kind of definition of both these are very similar in both cases it's what

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type of valuable if you mean what type of value a variable will refer to.

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So the interesting thing about type annotations and type inference is that they're kind of at odds with

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each other.

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In one case you and I are adding in a little bit of code to tell typescript what different types we

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are working with with type inference.

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We are relying upon typescript to do that work for us.

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So these two features are a question of are you and I are going to do everything manually or are we

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going to leave it up to typescript.

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That's what the big question here is.

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And that's what got what is going to be the big focus of our discussion about you know why we care about

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these features in went to use them.

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Let's take a quick pause right here.

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We're gonna come back the next video and start taking a look at a couple of different code samples.

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So a quick pause and I'll see you in just a minute.