Update README.md

Author: mgonzs13

README.md

@@ -1,12 +1,14 @@
 # Simple Node
 
-This is a new ROS 2 node to simplify the use of the spin and the executors. This way, service, actions and topics can be used as in ROS 1. Besides, this node also includes predefined action servers and one client to make its use more user-friendly to developers.
+This wrap uses the spin of an executor in a new thread. As a result, the calls of services and actions can be used synchronously. Besides, this node also includes predefined action servers and one client to make its use more user-friendly to developers.
 
 
 ## Examples
 
 ### Node
 
+This example shows how to create a node. To block the node, ```join_spin``` is used, which blocks the main thread till the thread of the spin ends.
+
 ```python
 from simple_node import Node
 import rclpy