Understanding Delta — The Most Important Option Greek

In this lesson, we take a deep dive into Delta, one of the most important concepts in options trading.

Delta tells you two key things: 

1. How much your option will move when the stock moves
2. The approximate probability that your option will expire in the money

Let’s say your call option has a Delta of 0.40. That means if the stock goes up $1, your option will go up around $0.40.
It also means there’s roughly a 40% chance your option will expire in the money. 

Whether you’re buying or selling options, understanding Delta helps you: 

• Choose better strike prices
• Understand the risk/reward of each trade
• Avoid beginner mistakes when entering positions

We also covered how Delta changes depending on how far in or out of the money the option is — and how that impacts your trading decisions. 

This lesson is part of our ongoing Yiddish series on mastering options trading — made simple. 

💬 Have a question? Drop it in the comments — it might become a future lesson!