What are the two types of system design?

Introduction

System design can be broadly categorized into High-Level Design (HLD) and Low-Level Design (LLD). These two types focus on different aspects of a system's architecture, offering complementary perspectives necessary for building a robust and scalable system.

High-Level Design (HLD)

Overview

HLD focuses on the big picture of the system architecture. It outlines how various components of the system interact, ensuring scalability, reliability, and efficiency.

Characteristics

• Abstract View: Provides an overview of the system without diving into implementation details.
• Main Components: Includes servers, databases, APIs, and third-party services.
• Focus Areas:
  • Scalability: How the system will handle increasing load.
  • Data Flow: High-level data movement between components.
  • Fault Tolerance: Ensuring the system remains operational during failures.
• Deliverables: Architecture diagrams, data flow diagrams, and component relationships.

Example

Designing a ride-sharing app like Uber at an HLD level would involve defining:

• A user service for handling profiles.
• A matching service for pairing drivers and riders.
• A location service for real-time tracking.
• Databases for user and ride data.

Recommended Resource

• Grokking System Design Fundamentals: Ideal for beginners building a strong foundation in HLD. Enroll Now

Low-Level Design (LLD)

Overview

LLD focuses on the details of individual components and their implementation. It involves designing classes, methods, and data structures to meet specific requirements.

Characteristics

• Detailed View: Breaks down each component into smaller parts for implementation.
• Focus Areas:
  • Class Design: Attributes, methods, and their relationships.
  • Algorithms: Specific steps for achieving functionality.
  • Data Structures: Efficiently managing data within the component.
• Deliverables: Class diagrams, sequence diagrams, pseudocode, and detailed documentation.

Example

For the same ride-sharing app, LLD would define:

• Classes for User, Driver, and Ride.
• Methods like matchDriver() and calculateETA().
• Data structures to efficiently store location and ride details.

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• Grokking the Coding Interview: Patterns for Coding Questions: Great for honing the skills needed in LLD. Enroll Now

Key Differences Between HLD and LLD

Recommended Resources

• Grokking the System Design Interview: Focused on HLD with real-world scenarios. Enroll Now
• System Design Mock Interview: Receive personalized feedback on both HLD and LLD. Start Mock Interviews

Final Tips

• Master Both: Understand the connection between HLD and LLD, as interviews often require both perspectives.
• Communicate Clearly: Articulate your HLD decisions first, then dive into LLD details if required.
• Practice Regularly: Work on real-world problems to strengthen your ability to switch between HLD and LLD effectively.

By focusing on these two types of system design and leveraging resources from DesignGurus.io, you can build the skills and confidence needed to excel in system design interviews.