1.People - This is the most crucial part in information system. Computer goals is to make end users (people) more productive in business, education, entertainment and etc.

2.Procedures- Its documentation are using, operating, and maintaining an information system.For example, procedures need to be established to run a payroll program, including when to run it, who is authorized to run it, and who has access to the output. In the autonomous computing initiative, data centres are increasingly run automatically, with the procedures embedded in the software that controls those centres.

3.Software- Software is a set of instructions that tells the computer what tasks to perform and how to perform them.Its divided into two main classes: system software and application software. Managing the hardware, data and program files, and other system resources and provides means for the user to control the computer, generally via a graphical user interface (GUI) are the things involved in the operating system which is the principal of system software.Application software is programs designed to handle specific tasks for users. Nowadays,we can see that smartphone apps became a common way for individuals to access information systems. Other examples include general-purpose application suites with their spreadsheet and word-processing programs, as well as “vertical” applications that serve a specific industry segment—for instance, an application that schedules, routes, and tracks package deliveries for an overnight carrier. Larger firms use licensed applications developed and maintained by specialized software companies, customizing them to meet their specific needs, and develop other applications in-house or on an outsourced basis. Companies may also use applications delivered as software-as-a-service (SaaS) from the cloud over the Web. Proprietary software, available from and supported by its vendors, is being challenged by open-source software available on the Web for free use and modification under a license that protects its future availability.

4.Hardware- Hardware is the physical aspect of computers, telecommunications, and other devices. The term arose as a way to distinguish the "box" and the electronic circuitry and components of a computer from the program you put in it to make it do things.Hardware implies permanence and invariability. Software or programming can easily be varied. You can put an entirely new program in the hardware and make it create an entirely new experience for the user. You can, however, change the modular configurations that most computers come with by adding new adapters or cards that extend the computer's capabilities.Hardware is a collective term. The cables, connectors, power supply units, and peripheral devices such as the keyboard, mouse, audio speakers, and printers also included in hardware not only the computer proper .Hardware is sometimes used as a term collectively describing the physical aspects of telephony and telecommunications network infrastructure.

4.Data- Information that has been translated into a form that is efficient for movement or processing.The form here means the binary digital form.However, a conversion need to be done first.In describing data that in its most basic digital format ,the term of raw data is used.Data also can accept to be used as a singular object or a plural object.Based on applying two-value Boolean logic to electronic circuits,the binary digital concepts formed.Today,Binary digit formats underlie the CPUs, semiconductor memories and disk drives, as well as many of the peripheral devices common in computing.Early computer input for both control and data took the form of punch cards, followed by magnetic tape and the hard disk. 

As a conclusion,all the five parts play an important role in information system.People play parts in people,procedures.software and hardware.