Take a look at the X-ray image below.
Yes, that shows a chainsaw embedded in a man’s body, with the chain dragged through his flesh. Amazingly, he survived! You can read all about it here.
Chainsaws are extremely useful tools – indispensable for many tasks – but they’re also deadly dangerous, particularly to those who don’t know what they’re doing with them. If you have one but haven’t had instruction from someone who knows and understands the dangers, may I strongly recommend that you seek such training as soon as possible? I’ve seen a number of people very badly hurt (some to such an extent that they were permanently crippled) when they tried to use chainsaws (even small ones) to clear away debris after a hurricane. The injury shown above was caused to a professional, who did understand the dangers, but nevertheless had his saw ‘kick back‘ at him. It can happen to anyone using these tools.
Please, folks, be careful out there. I seriously recommend printing out a copy of that X-ray image, laminating it, and securing it to your chainsaw handle. It’ll be a reminder to you every time you pick it up of what might happen if you’re not careful.
EDITED TO ADD: I found the US Forest Service training materials for chain- and crosscut saw operation online. They include manuals for students and instructors and PowerPoint presentations on how to safely use these tools. If you can’t get to one of the many chainsaw safety courses offered nationwide, those documents are a good place to learn the basics of chainsaw safety. There are also many videos on YouTube that will help.