The chocolate maker starts by roasting the beans to bring out the flavor. Different beans from different places have different qualities and flavors, so they are often sorted and blended to produce a distinctive mix. All seeds contain some amount of fat, and cocoa beans are no different. However cocoa beans are half fat, which is why the ground beans form a liquid. The difference between peanut oil and cocoa oil is that peanut oil is liquid at room temperature while cocoa oil is a solid up to about 90 degrees Fahrenheit.
Chocolate liquor is pure, unsweetened chocolate.
Eaten in this state it is pretty nasty because it is bitter, but it is possible to acquire a taste for it. When the high-fat cocoa beans are ground, they form chocolate liquor. You can do two different things with chocolate liquor. You can pour it into a mold and let it cool and solidify. This is unsweetened chocolate.