You need not know the internals for how a container converts JSP to a servlet. But you need to have an understanding of where and how the scriplets and expressions used in JSP fit into the servlet after translation. This is imp as based on these, the behaviour of the page changes.
Example:
If I have
The
String name becomes an instance variable of servlet after conversion and hence not
thread safe.
But if I update the above code to:
The String name becomes a member variable. Now it is thread safe.
This is the kind of understanding of JSP to servlet conversion one should have. Of course, I have just given one example. There are more to it which any study guide would touch upon.