Americano - add espresso to a mug and add hot water.
Long Black - add hot water to the mug, gently float espresso across the top.
I think I'm not really having a long black. Even though I pour the espresso in after the water, I'm not gentle. Also, I use way less water than what I've read about online. My drink seems very close to a plain espresso, just 40% of it is water.
It all started after a mistake. I had been heating up my cup with water from the wand, tossing it out, and then pouring in the espresso. One day, I forgot to pour it out. I liked that I had more to drink, so I kept it up.
And then there's the variant that I switched to that probably has no name; I call it the "Medium Chaos". I add a small amount of warmed half-and-half to my cup. Then I use the steam wand to shoot the water into it. Finally, I pour in the coffee. I get creamy, bubbly froth intertwined with strands of crema. I think it's lovely and delish; I might be alone in that.
Today I messed up. I added the coffee to the half-and-half. Then I realized I had forgotten the water. So, I shot in the water. The coffee frothed up with the half-and-half; it wasn't very nice, but I forced myself to choke it down. I call that one the "Medium Mistake".