Welcome. This is a great place to learn a lot about many things. It's way more than political, though that is the main reason for DU.
Most people here are great. There's a few who seem to enjoy confrontation and putting people down. I ignore them.
I participate mostly in the Photography Forum. I've learned tons there and every person I've met there is super-supportive. From amazingly talented photographers to new point and click people - all are welcome and all learn a lot from each other.