So a big debate that is heard a lot is whether to use Exploratory testing or Scripted. Exploratory testing is where you go in and you search the app specifically looking for bugs. You are going to search anywhere and everywhere based on the design. You will also try things out side the design. Basically think of it as you are on a safari hunting for bugs. You are exploring new territory looking for things that are out of the ordinary. This is a very widely used way of testing and also very popular.
What is Scripted testing? Well script testing you have a set script based on the design and how QA will be testing the software. With this you can get through and make sure certain points are hit. If something needs to be tested then you add it to the script. This is what you use a test plan for and you can read more about that in my first couple blogs. Think of it as a play and if it does not go a written put in a bug.
What are the benefits of using both? There is more benefits to using both then there are to not using one or the other. Scripted is really good and getting a through test but may miss something. Exploratory will help you find what you are missing but is no where near as through. This in hopes makes our below pie chart have less not found.
Conclusion: Use both in everyday testing.