Requirement engineering is a process of specifying, analyzing, and checking provided services and constraints of a system. ... In software development, imprecision in the requirement specification also causes many problems. Formal specification methodologies, however, require the requirements to be described precisely.

What do you mean by requirements specification?

A Requirement Specification is a collection of the set of all requirements that are to be imposed on the design and verification of the product. The specification also contains other related information necessary for the design, verification, and maintenance of the product.

What do you mean by requirement engineering?

Requirements engineering is the process of eliciting stakeholder needs and desires and developing them into an agreed-upon set of detailed requirements that can serve as a basis for all subsequent development activities.