What LLD covers vs HLD - Quick Revision & Key Differences

Recall & Review

beginner

What does HLD stand for and what is its main focus?

HLD stands for High-Level Design. It focuses on the overall system architecture, major components, and their interactions, giving a big picture view without going into details.

beginner

What does LLD stand for and what does it cover?

LLD stands for Low-Level Design. It covers detailed design aspects like class diagrams, data structures, algorithms, and how each component works internally.

beginner

Which design level focuses on component interactions and system modules?

High-Level Design (HLD) focuses on component interactions and system modules, showing how parts fit together.

beginner

Which design level includes class diagrams and method details?

Low-Level Design (LLD) includes class diagrams, method details, and internal logic of components.

intermediate

Why is it important to have both HLD and LLD in system design?

HLD gives a clear overview to understand the system structure, while LLD provides detailed instructions for developers to implement the system correctly.

What is the primary focus of High-Level Design (HLD)?

A Writing code and unit tests

B Detailed class diagrams and algorithms

C Database schema optimization

D Overall system architecture and major components

HLD focuses on the overall system architecture and major components, not detailed implementation.

Low-Level Design (LLD) typically includes which of the following?

A System modules and their interactions

B User interface wireframes

C Class diagrams and method details

D Project timelines and milestones

LLD includes detailed design like class diagrams and method details.

Which design phase helps developers understand how to implement the system?

A High-Level Design

B Low-Level Design

C Requirement Gathering

D Testing

LLD provides detailed instructions for developers to implement the system.

Which design level is more abstract and less detailed?

A High-Level Design

B Unit Testing

C Code Review

D Low-Level Design

HLD is more abstract and focuses on the big picture.

Which of these is NOT typically part of Low-Level Design?

A System architecture overview

B Algorithms

C Data structures

D Class methods

System architecture overview is part of High-Level Design, not LLD.

Explain the differences between High-Level Design (HLD) and Low-Level Design (LLD).

Think about big picture vs detailed instructions.

Why do software projects need both HLD and LLD phases?

Consider the roles of overview and detail in design.