High Level Design (HLD)
Low Level Design (LLD)
|High Level Design in short called as HLD.
|Low Level Design in short called as LLD.
|It is also known as macro level/system design.
|It is also known as micro level/detailed design.
|It describes the overall description/architecture of the application.
|It describes detailed description of each and every module.
|High Level Design expresses the brief functionality of each module.
|Low Level Design expresses details functional logic of the module.
|It is created by solution architect.
|It is created by designers and developers.
|Here in High Level Design the participants are design team, review team and client team.
|Here in Low Level Design participants are design team, Operation Teams and Implementers.
|It is created first means before Low Level Design.
|It is created second means after High Level Design.
|In HLD the input criteria is Software Requirement Specification (SRS).
|In LLD the input criteria is reviewed High Level Design (HLD).
|High Level Solution converts the Business/client requirement into High Level Solution.
|Low Level Design converts the High Level Solution into Detailed solution.
|In HLD the output criteria is data base design, functional design and review record.
|In HLD the output criteria is program specification and unit test plan.