A requirements definition is used by customers and end- users. It must
be written in a language which they can understand
Rationale for a requirement should be included in a requirements
definition
Requirements should be written so that they may be verified
4.4.0.0 Key points
Requirements specifications are intended to precisely communicate the
system functions and constraints. They may be written in some form
of structured language
Three classes of non-functional requirement are product requirements,
process requirements and external requirements
Natural language is normally used to write non- functional
requirements because of their variability and complexity