Functional Programming in Ruby for people who don’t know what functional programming is

I have a habit of throwing myself into the deep end, and this post is the result of one such occurrence. On Monday, I’ll attend a Meetup called “Functional and Dysfunctional Programming in Javascript”. The organizer asked if anyone could give a short talk about functional programming in other languages. “I could give Ruby a shot,” I said. Why? I have no idea. I don’t know anything about functional programming in Ruby (lambdas? what are those?) But I’ve become interested in functional programming lately, so why not? Let’s rock.