High Level Design (HLD)
概要设计说明是指系统的总体设计。它是对应用程序的总体描述。包括系统架构设计、数据库设计、系统、服务、平台及模块间关系的简要描述。它也被称为宏级/系统设计。它是由解决方案架构师创建的。它将业务/客户端需求转换为高级解决方案。它是在详细设计说明(LLD)之前建立的。
Low Level Design (LLD)
简单地说，详细设计说明就像详细的HLD意味着它指的是组件级设计过程。它对每个模块进行了详细的描述，意味着它包含了每个系统组件的实际逻辑，并深入到每个模块的规范中。这也被称为微观层次/详细设计。它是由设计师和开发人员创建的。它将概要解决方案转换为详细解决方案。它是概要设计说明之后创建。
| HLD | LLD |
| HLD是指系统的总体设计。 | LLD就像细化HLD意味着它指的是组件级设计过程。 |
| 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. |
ref: https://www.geeksforgeeks.org/difference-between-high-level-design-and-low-level-design/