How has the software analysis method evolved?

Far away, strong onlookers.

05 The business courtyard took a look at the leisure.

This classmate is in the first class of SIAS 07 software engineering, and there is no ready-made answer on the Internet, so summarize it yourself.

This one downstairs, you're a teacher, right? Students don't, ask what's wrong on the Internet, really.

Oh, I'm watching, not from our class.

Uh、、、 keep watching... It's miserable.

Software is developed and evolved from the concept of computer programs and program design, and is formed in the process of programs and program design developing to a certain scale and gradually commercializing. Software development has gone through the evolution of the programming phase, the software design phase, and the software engineering phase.

Programming phase.

The programming phase appeared in 1946 and 1955. The characteristics of this stage are: there is no concept of software yet, the programming is mainly developed around hardware, the scale is small, the tools are simple, there is no clear division of labor (developers and users), the programming pursues space-saving and programming skills, there is no documentation (except for the program list), and it is mainly used for scientific computing.

Software design phase.

The software design phase appeared in 1956 and 1970. This stage is characterized by a relatively stable hardware environment and the emergence of a "software workshop" development group.

Software. Woven form. The concept of software was established by the widespread use of product software (available for purchase). With the development of computer technology and the increasing popularity of computer applications, the scale of software systems is becoming larger and larger, high-level programming languages are emerging in an endless stream, the application fields are constantly expanding, developers and users have a clear division of labor, and the demand for software in society has increased dramatically.

However, there is no major breakthrough in software development technology, the quality of software products is not high, and the production efficiency is low, which leads to the "software crisis".

The development of software production can be divided into three eras: (1) the era of programming: During this period, the production of software was mainly the production mode of individual manual labor.

2) The era of program system: due to the continuous expansion of the application field of computers, the demand for software is also growing, and the software becomes complex due to the expansion of the problem domain of processing, and the designer has to form a small group of individual manual labor to cooperate, forming a workshop-style production mode and a small group of cooperative production program system era. (3) Software Engineering Era:

The mode of production in the era of software engineering is to adopt the concepts, principles, techniques, and methods of engineering, and to develop software using databases, development tools, development environments, networks, distributed, and object-oriented technologies.

The beginnings of software can be traced back to the fifties of the last century. In the early fifties of the last century, the first generation of tube computers came out, most of the computers at this time had amazing hardware power consumption, huge size, relatively simple computing power, and the prototype of the software was originally in the paper tape to punch holes to represent "0", "1" **. The real beginning of software history began in laboratories in the United States and Europe, when programmers wrote programs directly into computers in assembly language that was indecipherable to non-specialists.

In the sixties of the last century, the computer computing speed is getting faster and faster, the first is getting cheaper and cheaper, the new crystal computer is emerging, the speed has reached millions of operations per second, with the emergence of high-level languages for compiling software, the software industry is independent from the computer industry, becoming a rookie.

In the seventies and eighties of the last century, large-scale integrated circuit computers were introduced. The computing power of computers has been further enhanced, supercomputers with tens of millions of times per second have begun to enter all fields of scientific research, production, and social life, and the software industry has developed rapidly, and has gradually become the most active field of the information revolution.

Since the eighties of the last century, the era of intelligent electronic computers has come, and the computers of this era have begun to have the ability to learn and reason, and the computer has been able to understand natural language, sound, text and images, and can think, associate, reason, and draw conclusions, so it can solve complex technical problems, and also has the ability to collect, memorize, and retrieve relevant knowledge, during which software plays a vital role.

Mechanical languages, high-level languages, visual programming. Isn't that asking this?