1. Purpose
   1. To store data & to carry data for all of our testings.
2. Tags
   1. <suite>: have one or more tests.
   2. <test>: have one or more classes.
   3. <class>: have one or more methods.
   4. <methods>: contain one or more <include> tags
3. XML File
   1. Gives us a picture on why the annotations execute in a particular order.