diff --git a/API.md b/API.md
index ac91d057..fe4be2dd 100644
--- a/API.md
+++ b/API.md
@@ -10,6 +10,8 @@ This section explains all the used groups in this subgame.
 * `dig_by_water=1`: Blocks with this group will drop when they are near flowing water
 * `cultivatable=2`: Block will be turned into Farmland by using a hoe on it
 * `cultivatable=1`: Block will be turned into Dirt by using a hoe on it
+* `flammable`: Block helps spreading fire and gets destroyed by nearby fire (rating doesn't matter)
+* `soil=1`: Saplings and other small plants can grow on it
 
 ### Groups (mostly) used for crafting recipes
 
@@ -22,10 +24,19 @@ This section explains all the used groups in this subgame.
 * `wood=1`: Oak Wood Planks, Birch Wood Planks, etc. (only full blocks)
 * `wood_slab=1`: Slabs made out of a kind of wooden planks
 * `wood_stairs=1`: Stairs made out of a kind of wooden planks
-* `coal=1`: Coal of any kind (coal lump)
+* `coal=1`: Coal of any kind (lumps only, not blocks)
 * `boat=1`: Boat
+* `wool=1`: Wool (only full blocks)
+* `carpet=1:` (Wool) carpet
 
 ### Other groups
 
 * `water=1`: Water
 * `lava=1`: Lava
+* `liquid`: Block is a liquid
+    * `liquid=1`: Unspecified type
+    * `liquid=2`: Water
+    * `liquid=3`: Lava
+* `clock=1`: Clock
+* `compass`: Compass (rating doesn't matter)
+* `rail=1`: Rail