Okay, let's go over the fundamental basics of lava in the game Minecraft. You'll see here, I've set up a trench and poured some lava in it. It travels three blocks away. Lava travels much slower and a much shorter distance than water does. Now this lava is only one source block. So what that means is if I put it out with water here, I'll only get one block of obsidian. These other two blocks become cobblestone. One source block of lava to make one obsidian and two blocks flowing away to make cobblestone. One thing to remember about lava is that you can't make an eternal spring like you can with water. If I place two blocks of lava in this two by two hole, all I get are two source blocks and two blocks of lava moving away. In other words, two blocks that would become obsidian and two blocks that would become cobblestone and should I pick one up, they do disappear.
One use that lava has in Minecraft is as a garbage disposal. If I scroll to my cobblestone and press Q to drop it into the lava, it immediately disappears whereas if I drop it somewhere else, that block will float there for five minutes and look kind of ugly. This I can use to immediately get rid of items but be careful. As you can see, lava also emits light so it's a great alternative to torches and it can be used to make really beautiful sculptures. So there you go. Those are the fundamental basics of lava in the game Minecraft.