diff --git a/libqtile/widget/memory.py b/libqtile/widget/memory.py
index 83ba7a04..a10ce28a 100644
--- a/libqtile/widget/memory.py
+++ b/libqtile/widget/memory.py
@@ -32,10 +32,15 @@ def get_meminfo():
 
 
 class Memory(base.InLoopPollText):
-    """Displays memory usage"""
+    """Displays memory usage
+
+MemUsed: Returns memory in use
+MemTotal: Returns total amount of memory
+MemFree: Returns amount of memory free
+"""
     orientations = base.ORIENTATION_HORIZONTAL
     defaults = [
-        ("fmt", "{MemUsed}M/{MemTotal}M", "Formatting for field names")
+        ("fmt", "{MemUsed}M/{MemTotal}M", "Formatting for field names. Named modeled after Linux /proc, but portable with other Unices")
     ]
 
     def __init__(self, **config):
diff --git a/libqtile/widget/swap.py b/libqtile/widget/swap.py
index ca1138e9..e5f60b97 100644
--- a/libqtile/widget/swap.py
+++ b/libqtile/widget/swap.py
@@ -33,7 +33,11 @@ def get_swapinfo():
 
 
 class Swap(base.InLoopPollText):
-    """Displays memory usage"""
+    """Displays swap usage
+SwapUsed: Returns swap used
+SwapTotal: Returns total amount of swap space
+SwapFree: Returns amount of swap free
+"""
     orientations = base.ORIENTATION_HORIZONTAL
     defaults = [
         ("fmt", "{SwapUsed}M/{SwapTotal}M", "Format field names")