diff --git a/D3.md b/D3.md
index f3cddd6..43a75b1 100644
--- a/D3.md
+++ b/D3.md
@@ -118,6 +118,7 @@
 		- callback will be executed for each DOM element
 		- `d` is data for the current element
 		- `i` is the index of that element in the array
+	- `.exit().remove()` examines visual elements that are not bound to data and removes them
 
 ## Linear Scale
 
@@ -293,3 +294,8 @@ function dragStart(d){ //d is the data for the dragged object
 ```
 
 You can use the xScale.invert and yScale.invert to get data from d3.event.x and d3.event.y
+
+
+## Basic Layouts
+- https://github.com/d3/d3/wiki/Plugins
+- http://c3js.org/