A program is a series of operations and control constructs. Essentially, programs are static representations of the dynamic changes to data. If copy fails because a ile with the output file name exists, the program deletes that old file, and re-executes copy. The outer rectangle enclosing the operations represents the loop, and the little black square and diverging lines represents a conditional branch. Data are represented with familiar icons.
Operations consist of a name followed by data icons.
Control constructs are represented with keywords and indentation. A program is a list of commands and control constructs. Essentially, programs describe how data is manipulated. The program in Fig. 1 represented in the text-based language.