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A trait represents a capability, something that a type can do and can be shared with other types.

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We can use traits to define shared behavior in an abstract way.

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So let's create a trait just to see how it's done.

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So all we have to do is use the trait keyword followed by the name we want our trait to be.

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So we're going to create an overview trait.

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And in this trait we're going to define a function.

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Hold overview.

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That is going to refer to itself.

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And return a string.

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And then to use this trade.

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You can actually implement it in with a type.

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So let's create a struct.

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And we're going to call it course.

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And then in here we're going to have a headline which is a string, and then the author, which is also

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a string.

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And then I'm going to go ahead and create another course.

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Is going to implement the same two things.

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So in here, what we're going to do is we're going to implement overview for course.

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And we're going to say an overview.

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So if we're going to return a string and then in here, we're going to say we're just going to format

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out.

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And then we're just.

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We just want to.

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To self.

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Dot author and self dot headline.

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So just something really easy for us to do.

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And then we want to do the same thing.

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For.

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Another course.

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So as you can see, we were able to implement the overview trait for two different types, which is

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exactly what we want to be able to do with the trait and exactly what the definition of a trait is.

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But something that we can do is we can actually have a default implementation for our trait.

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So in here we're going to say we have a string from and then we want it to say this is a rust course.

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So now if we come down here, let's create a couple of our structs and we'll say Let.

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Course.

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One equal to course.

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And then we're going to have our headline is a string from headline.

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And then our author is a string from Tyler.

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And then we want to do the same thing again.

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Except this time we want it to be for another course.

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Another course and we'll say another headline.

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And another.

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Tyler.

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All right.

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So good.

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So we have no airs there so far.

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So let's create a print and say course one dot overview.

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So we're referencing we're calling the trait that we implemented.

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And then in here.

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Let's say, of course, to dot overview.

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And now let's run it.

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So we see Tyler headline.

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Which is what we implemented up here for course.

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And then we also see another Tyler, another headline, which is what?

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We the the values that we gave down here.

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So now how can we use our default thing?

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Because we currently are overriding it.

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So let's just go ahead and delete all of this.

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So now we just say implement overview for course, and we took out our implementation for it.

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So now if we run it, we actually see this is a rust course, which is the default implementation for

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it, and that's how traits work.

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So let's see what else that we can do with traits in the coming lectures.