So just like with market demand and supply, we learned how to shift the curves left and right. We already discussed how to shift aggregate demand. Now let's see how we shift our short run aggregate supply. So, there's going to be factors that change other than the price level affecting our aggregate supply, right? So now we're thinking about our short run aggregate supply curve and what factors can affect it to make it shift left or right. Okay? Aggregate supply is different in the short run and in the long run. And one thing we said about the long run—So over here, I want to say something about the long run. Remember that we had this straight up and down curve because it was fixed in the long run how much we were going to be able to produce based on what's available in the economy, right? So in general, what we see in the long run is shifts to the right. In for the most part, over time, we see shifts to the right because of things like technology increasing. There are just general increases, increases in population. There's just usually more and more. There has to be some sort of event causing it to shift to the left that will shift our long run to the left, right? But in general, what we see is it shifting to the right just because of a general increase in resources such as labor, from more population, better technology, things like that. In the short run, we're going to see a few different things coming into play. Okay? So the short run, we're going to deal with this curve. Remember that we have in the short run. So I'm going to draw 2 graphs here. And remember, we had our short run aggregate supply looking something like this. Right? And, what were our axes on these graphs? We have our price level. Remember, price level throughout the economy and real GDP, the quantity of goods and services being produced in the economy. Same thing over here. Okay? So when we talk about shifting these curves, we're going to use that same idea of something good happening for short run aggregate supply, something bad happening for short run aggregate supply. Right? So let's start over here with something good happening. Right? If something good happens, what's going to happen? We're going to shift to the right. Right? We say good things shift our curve to the right. And if that's our first curve, well our new curve is going to be somewhere over here, right? Somewhere to the right. And if something bad happens for short run aggregate supply, well, we're going to shift that curve to the left. So it would go this way, and we would have our new short run aggregate supply somewhere to the left. So if this is aggregate 1 and here's 2. Right? So that's something you should be familiar with from when we were shifting curves earlier in the course, right? But now, we're going to be dealing with it on the aggregate level. So let's see what could be some of the reasons that this short run aggregate supply could shift to the left or to the right. Cool? Let's pause here and do that.