The fortress named (randomly) Leaftome is coming along nicely. It's nearly the end of the first year, and things are chugging along.
You can see in the middle where we've cut into the mountain and built out fortress. The red to the south west of the fortress is a magma vent. The black to the south east is unexcavated mountain. The green to the north is the side of the hill on the same level, the darker green is the next level down, and the blue is even further down. Dwarf fortress is 2D layers pancaked on top of eachother that interact, so an item that drops through the ground on one level will turn up on the next level down (unless you dug a hole through that layer too)
There is a farming plot one level down for food, but everything else is on this one level. I suspect things are going well, because two of my dwarves (one, a legendary miner) have paired up, and reading their thoughts relates that they are pretty damn happy. Ever since I figured out brewing produces seeds and cooking makes seeds edible, food and beer stores have been extremely full. Before, I would eat the food, leaving seeds, and it would throw off my numbers to have uncooked food (seeds) around. Suddenly my dwarves would be starving, and I wouldn't know why.
I had plenty of magma to access, but with the magma vent full of fire imps and magma men, I was afraid of fiddling around with floodgates before I knew what stone would melt under the heat, and flood my fortress with lava. I settled on setting up a series of floodgates to manage some water I drained from a lake a few levels up, so I could allow the lava to flow into a small channel I dug, and then pour water on just the opening, cooling the lava, and sealing access from the magma vent to the soft underbelly of my fortress.
Since Dwarf Fortress is a roguelike, it only uses characters to represent the elements of the game. This often leaves non-players wondering what the hell they're looking at. So for an explanation to what you're seeing, click on the next image.
Liquids (water and magma) are shown by their depth. 7 being the space is full completely of the liquid, and 1 being there is a minor puddle of the liquid. Fluid dynamics are entirely in place, and affected by gravity, and the multiple layers. Were I to cut into the retaining wall of the magma vent, the space I opened would spill out under liquid pressure, and try to spread all seven layers out to one layer in any open area it could expand into. Of course, when that space goes down a layer, the lava space next to that layer, goes down a layer into the first space, causing the entire layer of magma to spill into any open areas of my fortress. Of course, if there was one or more layers of magma above that layer, it would drain out the opening too, until it leveled off. Like poking a hole in the side of a water bottle. Pretty impressive stuff.