Nassi–Shneiderman diagram

[1] This type of diagram was developed in 1972 by Isaac Nassi and Ben Shneiderman who were both graduate students at Stony Brook University.

Nassi–Shneiderman diagrams reflect this top-down decomposition in a straightforward way, using nested boxes to represent subproblems.

Consistent with the philosophy of structured programming, Nassi–Shneiderman diagrams have no representation for a GOTO statement.

Their abstraction level is close to structured program code and modifications require the whole diagram to be redrawn, but graphic editors removed that limitation.

They were included in Microsoft Visio and dozens of other software tools, such as the German EasyCODE.

First is the simple True/False or Yes/No branching block which offers the program two paths to take depending on whether or not a condition has been fulfilled.