Deborah Melkin concludes a video series on how to get execution plans in SQL Server:
I really wanted to put this together because I feel like understanding these differences is important to understanding how we can troubleshoot performance problems and where we need to be looking for these pieces of information to get that full picture of where to spend our time. It makes us better performance tuners. I hope you found this helpful and you leave with a better appreciation for these nuances.
Click through for the video, as well as a transcription on the blog post.