What LLD covers vs HLD - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to identify what HLD focuses on.

LLD

HLD mainly describes the system's [1] and its major components.

Drag options to blanks, or click blank then click option'

Aarchitecture

Bcode

Cvariables

Dfunctions

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing HLD with detailed coding.

HLD (High-Level Design) focuses on the overall architecture and major components of the system.

2fill in blank

medium

Complete the code to identify what LLD focuses on.

LLD

LLD details the [1] and logic inside each component.

Drag options to blanks, or click blank then click option'

Aarchitecture

Bnetwork setup

Cdeployment

Dinternal design

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing LLD with deployment or network details.

LLD (Low-Level Design) focuses on the internal design and logic of components.

3fill in blank

hard

Fix the error in the statement about HLD and LLD.

LLD

HLD shows [1] of each module.

Drag options to blanks, or click blank then click option'

Aarchitecture

Bcode

Cdatabase schema

Duser interface

Attempts:

3 left

💡 Hint

Common Mistakes

Thinking HLD includes code details.

HLD does not show detailed code but focuses on architecture and major components.

4fill in blank

hard

Fill both blanks to complete the comparison between HLD and LLD.

LLD

HLD focuses on [1], while LLD focuses on [2].

Drag options to blanks, or click blank then click option'

Asystem architecture

Bdetailed design

Cnetwork protocols

Dhardware setup

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing network or hardware with design levels.

HLD focuses on system architecture; LLD focuses on detailed design inside components.

5fill in blank

hard

Fill all three blanks to describe the focus areas of HLD and LLD.

LLD

HLD defines [1], [2], and [3] of the system.

Drag options to blanks, or click blank then click option'

Amajor components

Bhigh-level algorithms

Coverall architecture

Dinternal logic

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing detailed logic with HLD focus.

HLD defines overall architecture, major components, and sometimes high-level algorithms.

Practice

1. Which of the following best describes what High-Level Design (HLD) focuses on?

easy

A. Database schema and indexing details

B. Detailed class structures and method implementations

C. Writing code for individual modules

D. The overall system architecture and main components

Solution

1. Step 1: Understand HLD purpose

   HLD is about the big picture, showing main parts and how they connect.

2. Step 2: Compare options

   Only The overall system architecture and main components describes overall architecture and main components, which matches HLD.

3. Final Answer:

   The overall system architecture and main components -> Option D

4. Quick Check:

   HLD = overall system view [OK]

Hint: HLD = big picture, LLD = details [OK]

Common Mistakes:

• Confusing HLD with detailed coding
• Thinking HLD includes method-level details
• Mixing database design with HLD focus

2. Which of these is typically included in Low-Level Design (LLD)?

easy

A. System component interactions

B. User interface wireframes

C. Class diagrams with methods and attributes

D. Network topology diagrams

Solution

1. Step 1: Identify LLD details

   LLD focuses on detailed design like classes, methods, and data structures.

2. Step 2: Match options to LLD

   Class diagrams with methods and attributes describes class diagrams with methods and attributes, which fits LLD.

3. Final Answer:

   Class diagrams with methods and attributes -> Option C

4. Quick Check:

   LLD = detailed class design [OK]

Hint: LLD = classes and methods details [OK]

Common Mistakes:

• Choosing high-level diagrams for LLD
• Confusing UI design with LLD
• Mixing network diagrams with LLD

3. Given a system design process, which step correctly uses HLD and LLD?

medium

A. Write detailed code first, then create HLD diagrams

B. Create HLD diagrams to plan architecture, then LLD for coding details

C. Skip HLD and directly write LLD documents

D. Use LLD to explain user requirements

Solution

1. Step 1: Understand design flow

   Good practice is to start with HLD for overall planning, then LLD for detailed design.

2. Step 2: Evaluate options

   Create HLD diagrams to plan architecture, then LLD for coding details matches this flow: HLD first, then LLD for coding guidance.

3. Final Answer:

   Create HLD diagrams to plan architecture, then LLD for coding details -> Option B

4. Quick Check:

   Design flow = HLD then LLD [OK]

Hint: Plan big picture first (HLD), then details (LLD) [OK]

Common Mistakes:

• Starting with code before design
• Skipping HLD and losing overview
• Using LLD for user requirements

4. A developer wrote detailed class diagrams but missed showing system modules and their interactions. What design level is missing?

medium

A. High-Level Design (HLD)

B. Low-Level Design (LLD)

C. Both HLD and LLD

D. Neither HLD nor LLD

Solution

1. Step 1: Analyze given design

   Detailed class diagrams are part of LLD, but system modules and interactions belong to HLD.

2. Step 2: Identify missing design level

   Since modules and their interactions are missing, HLD is incomplete.

3. Final Answer:

   High-Level Design (HLD) -> Option A

4. Quick Check:

   Missing modules = missing HLD [OK]

Hint: Modules and interactions belong to HLD [OK]

Common Mistakes:

• Confusing class diagrams with HLD
• Thinking LLD covers system modules
• Assuming both designs are missing

5. You are designing a new feature for a large system. Which approach correctly uses HLD and LLD to ensure scalability and maintainability?

hard

A. Design the system modules and their interactions first, then define classes and methods

B. Focus only on database schema and skip other designs

C. Write code immediately and document design later

D. Start with detailed class design, then create overall system diagrams

Solution

1. Step 1: Understand scalable design approach

   Good design starts with HLD to define modules and interactions, then LLD for detailed classes.

2. Step 2: Evaluate options for best practice

   Design the system modules and their interactions first, then define classes and methods follows this approach, ensuring clear structure and maintainability.

3. Final Answer:

   Design the system modules and their interactions first, then define classes and methods -> Option A

4. Quick Check:

   HLD first, then LLD for scalable design [OK]

Hint: Big picture first, then details for scalable design [OK]

Common Mistakes:

• Starting with code before design
• Ignoring system modules and interactions
• Focusing only on database schema