Delta is the first Greek most people learn, and the definition is simple: how much an option's price moves when the stock moves a dollar. What most explanations skip is that delta does not stay put. It drifts as expiration approaches, and that changes what a position does. Using a put vertical on Microsoft, this shows how the same two strikes behave differently with a week left than with six, why in the money options drift toward one while out of the money options fall toward zero, and how to use that when picking an expiration. Education, not a recommendation. 📊 tastylive: tastylive.com 📰 Get Tom's pre-market analysis every morning: tastylive.com/newsletters 📘 FREE Options Strategy Guide: tinyurl.com/bp9ms763 📱 Follow tastylive on X: x.com/tastyliveshow Chapters 00:00 What delta actually measures 00:50 Delta as a risk metric 01:22 Reading deltas on the chain 02:27 Choosing a vertical to trade 03:09 Watching the delta change 05:02 The the...