 In this course, we're going to look at time spreads. So time spreads are spreads where we use two different expiry series. So we're going to use different months in the same option spread. Let's first look at how a basic calendar works. And then we look at a double calendar. A time spread involves two different months. So we could be looking at the June series and the July series. This is also a non-directional strategy. So we're looking at just the basic calendar here. It starts off non-directional. So you're going to start off with a delta neutral or very close to delta neutral position. But depending on how the stock moves, your position is going to get a positive delta or a negative delta. It's a theta positive trade and it's also a vega positive trade. Now this is very interesting because there does not exist any other trade in options that are both theta positive and vega positive. So if you recall, I always mention your battle is always going to be between theta and vega. So if you're theta positive, you'll usually be vega negative. And if you're theta negative, you'll usually be vega positive. The calendar is very unique and in fact all the time spreads are theta positive and vega positive trades. So you're gaining in time decay and you'll also gain if volatility increases. So that's a very unique situation. And once we go into part two and look at the platform, we'll see how that works and why it is theta positive and why it is vega positive at the same time. Let's say we're looking at the June series and the July series. So you're going to sell the front month at the money strike price. Now it can be a call or a put, it doesn't matter. But you're going to sell the at the money front month option. And you're going to buy the back month, the back month would be the July at the same strike price. So it has to be the same strike price and usually it's going to be at the money.