What are DF Diagrams , and how they help project managers in their job?
As you can see, is a data flow diagram a diagram that shows the dataflow in an application.
At the highest level you have the context diagram that can be represented as:
+-------------+
input --> | Application | --> output
+-------------+
You can zoom into the function to show detailed dataflow:
+-------+ +--------+ +----------+
code --> | lexer | --> | parser | --> | treetool | --> grapical representation
+-------+ +--------+ +----------+
| ^ ^
| | |
| V |
| ================ |
+--> | symbol table | -----------+
================
As you see, there are functions and data stores. Functions can change the data and datastores are used to store and retrieve the data.