Business requirements are typically classified into three business requirements categories. The categories are functional requirements, non-functional requirements and design constraints. The definition of these categories are:
Describe the system features or things the system must do to support the end users business responsibilities. i.e. The system shall allow the ATM User to deposit funds into their individual bank account.
Describe properties the system must have (e.g. performance, availability, accessibility). What are the qualities the system needs to have for the user? i.e. The system shall provide an ATM transaction response time of 5 seconds.
There are four categories of non-functional requirements:
- Usability ease with which a user can learn to operate and usability design standards
- Reliability availability of the system, nightly backup, logs, nightly backup
- Performance maximum users, response time
- Supportability Error messages, error logs
Limits the development in some way. Such as, defining an operating system the system must run on, or defining which programming language must be used to implement the system. i.e. The ATM must have touch pad screens.
To learn more about how to elicit and write effective business requirements register for Piersons Virtual Business Requirements Gathering & Writing Class.