diff --git a/SmoulderingBeachBall/Domain.fs b/SmoulderingBeachBall/Domain.fs
index 286c5d8..d1687bc 100644
--- a/SmoulderingBeachBall/Domain.fs
+++ b/SmoulderingBeachBall/Domain.fs
@@ -1,18 +1,34 @@
 namespace SmoulderingBeachBall.Domain
 
     [<AutoOpen>]
+    /// A collection of types used to describe a Smouldering Beach Ball image. 
     module DomainTypes =
 
         open System.Drawing
 
+        /// <summary>
+        /// The type of overly the image should have.
+        /// Border creates a border around the base image.
+        /// Full creates a border and a 'X' over the base image.
+        /// </summary>
         type OverlayType =
             | Border
             | Full
         
+        /// <summary>
+        /// The specification for the overlay.
+        /// You define the overlays colour and overlay type here.
+        /// </summary>
         type OverlaySpec =
             { colour: Brush;
               overlayType: OverlayType }
-        
+
+        /// <summary>
+        /// The specification for the whole image.
+        /// Set the width, height, colour, save location and overlay here.
+        /// The overlay requires an OverlaySpec if an overlay is desired.
+        /// To create an image without an overlay, just use 'None'.
+        /// </summary>
         type ImageSpec =
             { width: int;
               height: int;
diff --git a/SmoulderingBeachBall/Services.fs b/SmoulderingBeachBall/Services.fs
index f394b55..c42b148 100644
--- a/SmoulderingBeachBall/Services.fs
+++ b/SmoulderingBeachBall/Services.fs
@@ -1,5 +1,6 @@
 namespace SmoulderingBeachBall
 
+/// Provides the public facing functions of Smouldering Beach Ball.
 module Services =
 
     open System
@@ -7,6 +8,12 @@ module Services =
     open InternalServices.Validation
     open InternalServices.Drawing
 
+    /// <summary>
+    /// Creates an image using the specification provided by the ImageSpec.
+    /// </summary>
+    /// <param name="spec">
+    /// The image specification which describes how the image should look.
+    /// </param>
     let makeImage (spec: ImageSpec) =
         async {
             try