Traditional Application Development:

The main goal of this section is to categorize business process management
systems from a software systems point of view into major developments that
information systems design underwent in the last decades. It depicts
the first stages in the evolution of information systems. The dates in that figure
provide only rough estimates�the respective systems architectures were not
uncommon at the dates given.
In the early days of computing, applications were developed from scratch,
without taking advantage of prior achievements other than subroutines of
fine granularity. Application programmers needed to code basic functionality
such as, for instance, access to persistent storage and memory management.
Basic functionality needed to be redeveloped in different applications, so that
application programming was a costly and inefficient endeavour. As a result
of the tight coupling of the programmed assembler code with the hardware,
porting an application to a new computer system results in a more or less
complete redevelopment.
Operating systems were developed as the first type of subsystem with
dedicated responsibilities, realizing separation of operating systems concerns
from the application. Operating systems provide programming interfaces to
functionality provided by the computer hardware. Applications can implement
functionality by using interfaces provided by the operating system, realizing
increased efficiency in system development.
Specific properties of the computer hardware could be hidden from the
application by the operating system, so that changes in the hardware could
bereflected by a modified implementation of the operating system�s interface, for
instance, by developing a new driver for a new hardware device. An operating
systems (OS) layer is depicted in as the lowest level subsystem.