Low-Level Design Interview Questions & Answers!! Are You Getting Ready to Ace anLow-Level Design Interview questions for a Low-Level Design Position? Here is a collection of useful interview questions and related answers.

By applying LLD to the top-level design, a comprehensive plan for data structures, interfaces, algorithms, and algorithms is generated. Step-by-step refining is applied to the component-level design.

Low-Level Design Interview Questions & Answers:

1. What is low-level design (LLD)?

Low-level design (LLD) involves designing small application components for business needs. It comprises gathering requirements, setting use cases, and applying NPD to create UML class, sequence, and activity diagrams.

2. What is the low-level design space?

Object-oriented code implementation employing design patterns ends in the low-level design space. This level entails learning design patterns like class object polymorphism inheritance abstraction in encapsulation and SOLID concepts.

3. What is low-level design in software development?

Low-level design (LLD) is a crucial aspect of software development life cycles that begins after high-level design (HLD). LLD provides detailed information about the components and their behavior.

4. What is the difference between high-level design and low-level design in software development?

High-level design (HLD) is a general system design that involves a trade-up between different frameworks, components, and databases. In contrast, low-level design (LLD) is a more detailed design that provides specific information about the components and their behavior.

5. During the HLD phase, what do developers do?

During the high-level design (HLD) phase, developers select a component, such as a load balancer, and define a user service and database. They also define the general way of designing a system without worrying about how actual code will work.

6. What does low-level design involve?

Low-level design (LLD) involves providing detailed information about the components and their behavior. This includes defining class diagrams, methods, structure, behavior, and responsibility.

7. What is the input for high-level design in software development?

In high-level design, the input is the requirement given to create the high-level design and select different components.

8. What is the input for low-level design in software development?

In low-level design, the input is the high-level design. Different components have their own behavior and structure, and when defined in the low-level design, these behaviors and structures are also present in the low-level design.

9. What is the value of low-level design for developers?

Low-level design (LLD) is a valuable tool for developers, as it allows them to write down logic or code for the component. This helps developers understand the behavior and structure of the component and write more efficient and effective code.

10. What are object-oriented principles?

Object-oriented principles are a set of guidelines or concepts Encapsulation, inheritance, polymorphism, abstraction. These principles help to ensure that software is well-designed and easy to maintain over time. Following these principles allows developers to produce software that is more robust, dependable, and efficient.

11. What is UML (Unified Modeling Language)?

In low-level design, components can have their structure and behaviors defined using UML, which stands for Unified Modeling Language. From a created power viewpoint, it aids developers in comprehending a component’s structure and behavior.

12. What are the different UML diagrams available?

There are various UML diagrams available, which can be useful for designing low-level designs. These diagrams can be categorized into two sections: structure UML diagrams and behavioral UML diagrams.

13. What are structure UML diagrams?

Structure Entity and object relationships can be depicted in UML diagrams. Parts’ structure and behavior can be better understood with the help of seven illustrations. The most helpful is the class diagram since it displays the relationships between classes.

14. What are behavioural UML diagrams?

A component’s operations are defined by behavioral UML diagrams. The seven behavioural design diagrams are sequence, use case, activity, state, interaction or flow, and time. Each figure shows component behavior.

15. Why are UML diagrams important in low-level design?

UML diagrams are essential tools for defining the structure and behavior of components in low-level design. By using these diagrams, developers can quickly convert high-level components into code and improve their overall design.

16. What is the process of converting diagrams into actual code in LLD?

Use object-oriented design (OOD) ideas, design patterns, and SOLID principles to translate these representations into code.

At this level, designers comprehend SOLIDprinciples, class object polymorphism, inheritance, abstraction, and encapsulation.

17. What is the advanced step of low-level design?

Advanced low-level design involves building testable, maintainable, refactored, production-ready code that may change. Advanced LLD approaches are used in companies where other developers generated source code.

18. What is the importance of object-oriented design (OOD) in code?

Object-oriented design (OOD) is a fundamental aspect of programming and is essential for creating a good object-oriented design (OOD). object-oriented design programming to promote modularity, reusability, and maintainability.

19. What is the importance of modularity in system design?

The importance of modularity in system design is that it allows for better organization and maintenance of the codebase. This means that the code can be easily modified or extended without affecting the rest of the system.

20. What is the importance of readability in system design?

The importance of readability in system design is that it allows other developers to easily understand the code and make changes or improvements. This means that the code should be well-documented and easy to read.

21. What is the importance of reusability in system design?

Developers can save time and effort by making use of pre-existing code components and libraries, which is why reusability is crucial in system design. Because of this, it’s important to make sure the code can be used in different projects.

22. What are the requirements for a reliable system design?

A reliable system design requires good error handling and robustness. This means that the system should be able to handle error situations and provide good information for users, even in unexpected circumstances.

23. What are some important factors that need to be considered in low-level design?

Some important factors that need to be considered in low-level design include concurrency handling, thread safety, data storage in a database, and ensuring atomicity of database transactions to prevent failures in inconsistent systems or data.

24. What is the importance of using data structures in object-oriented design (OOD)?

Using data structures in object-oriented design (OOD) is important as it tests one’s understanding of these concepts. It allows for better representation of the data in a single-dimensional array, which can be rendered into cross-platform graphics using line wrapping.

25. What is the importance of identifying classes, objects, methods, and properties in coding?

Identifying classes, objects, methods, and properties in coding is important as it helps developers create a well-designed and efficient game.

It is crucial to understand the relationship between these concepts in order to create a scalable and maintainable codebase.

26. What are SOLID principles in programming?

The SOLID principles are single responsibility, open-closed, Liskov’s Substitution Principle, interface segregation, and dependency inversion.

27. What is the single responsibility principle?

The single responsibility principle states that each class should have only one responsibility, which can be applied to various types of classes.

28. What is the open closed principle?

The open closed principle states that a class should be open for extension and closed for modification.

29. What is the Liskov’s Substitution Principle?

The substitution principle states that objects of a superclass should be replaceable with objects of its subclasses without affecting the correctness of the program.

30. What is the interface segregation principle?

The interface segregation principle states that a class should not be forced to depend on interfaces it does not use.

31. What is the dependency inversion principle?

The dependency inversion principle states that high-level modules should not depend on low-level modules, but both should depend on abstractions.

32. What is the importance of understanding and applying SOLID principles in low-level design?

Understanding and applying SOLID principles in low-level design is essential for creating a user-friendly interface that is easy to navigate and maintain. By following these principles, developers can create a more user-friendly and effective application of low-level design.

33. What exactly interface segregation in software design?

Interface segregation allows you to substitute child classes and base classes with child classes, enhancing the functionality of your application. It helps in maintaining and understanding the code.

34. How does interface segregation help in maintaining and understanding the code?

Interface segregation ensures that the code is less complex and more maintainable.

35. What is the substitution principle in software design?

The substitution principle states that when we are inheriting, we can use the child class, which should not be something that cannot hold the functionality of anyone. This principle makes code more flexible and maintainable.

36. What is a web application server in software design?

Web applications run on web application servers. Web developers use it to host and run web applications and inject dependencies and components by implementing a factory function.

37. What is the responsibility of creating new instances of an object in low-level design?

In low-level design, the responsibility of creating new instances of an object is given to the container, which takes care of the entire logic when it is instantiated.

38. How are activity diagrams different from sequence diagrams?

An activity diagram consolidates all the cases and flows into a single visual representation, while a sequence diagram depicts the objects to illustrate the design’s flow.

39. What is a code review?

The purpose of developers evaluating one other’s programs is to speed up software development, improve code quality, and discover flaws. One other name for it is peer-to-peer code review.

40. What is dependency injection in low-level design?

Dependency injection is a concept in low-level design where the entire logic is taken care of by the container.

41. What are the three steps in designing for lower-level design all the way up to code?

From low-level design to code, there are three stages: making a list of all possible user actions, drawing a use case diagram, and defining complicated behaviors.

42. What are the Layout patterns?

When creating software, design patterns are there to fix certain issues that crop up. These have already been tested and proven, which makes the design process much easier.

43. What is a use case diagram?

A use case diagram is a tool used in software engineering that notes down the actions that can be performed by a user.

44. What is a class diagram?

A class diagram captures the states and behaviours required for these actions, which are the variables that you usually have in a class or data entries in a database.

45. What is the point of following a set method when writing new code?
Following a step-by-step code development method helps you advance quickly. This technique makes coding faster, clearer, and more efficient and extendable.

Now, let’s be smarter in MCQ’S on LLD.

1) What is the concept of low-level design in software development?

1. A detailed design of the system’s overall architecture

2. General system design including framework, component, and database trade-offs

3. A design of the system’s user interface

4. A blueprint for the database structure of the system

2) What distinguishes high-level and low-level design?

1. Low-level design explains component behavior, while high-level design picks components and establishes user service and database.

2. Low-level design details the system’s architecture, while high-level design is broad.

3. The database structure is low-level design, while the user interface is high-level.

4. Database schema is high-level design, user interface is low-level.

3) What are the main components of low-level design?

1. Class diagrams, methods, structure, behavior, and responsibility.

2. User service, user, address, and profile.

3. Frameworks, components, and databases.

4. Requirements.

4) What is the main purpose of UML diagrams in low-level design?

1. To define the structure and behaviours of components.

2. To involve a trade-up between different frameworks, components, and databases.

3. To define a user service and database.

4. To provide an idea of how different classes have their correlation and link with each other.

5) What are the four UML diagrams that will be discussed in the next session?

1. Class diagram, sequence diagram, use case, and activity.

2. LLD, HLD, UML, class diagram.

3. Frameworks, components, and databases.

4. Requirements.

6) What is the NPD (New Product Development) technique used in low-level design?

1. Object-oriented principles and solid principles.

2. To provide an idea of how different classes have their correlation and link with each other.

3. To define the high-level design.

4. To involve a trade-up between different frameworks, components, and databases.

7) What is the advanced step-in low-level design?

1. Write testable, maintainable, refactored, production-ready code that can change.

2. Establish the high-level design.

3. User service and database definition.

4. To trade frameworks, components, and databases.

8) What is the importance of low-level design in creating a user-friendly interface?

1. To simplify the design of a single-dimensional array.

2. To ensure that each class has only one responsibility.

3. To define a user service and database.

4. To involve a trade-up between different frameworks, components, and databases.

9) What are the solid principles?

1. Single responsibility, open closed principle, Liskov’s Substitution principle, interface segregation, and dependency inversion.

2. multi-responsibility, open-closed, substitution, interface segregation, dependency inversion.

3. SOLID design patterns and software development methods.

4. NLP, text classification, and named entity recognition.

10) What is the open closed principle in software design?

1. A class should allow for changes but not extensions.

2. A class ought to be extensible but immutable.

3. One class should be open for changes and another should be closed.

4. A class can be either open or closed to extensions.

11) What is the single responsibility principle in software design?

1. Each class should have many duties.

2. should have one duty.

3. Every class should be responsible.

4. No classes should be responsible.

12) What is the substitution principle in software design?

1. It should inherit from a class that lacks its capability.

2. A class should inherit from a functional class.

3. Dependent classes can be replaced by any child class.

4. A class must inherit from an unreplaceable parent class.

13) Which of the following principles helps in maintaining and understanding the code?

1. Interface segregation

2. Tight coupling

3. Dependency inversion

4. Loose coupling

14) Creation of object instances is delegated by low-level design to?

1. Container

2. Developer

3. Compiler

4. Framework

15) Low-level design patterns include?

1. Creational, Behavioural, & Structural Patterns

2. Security Patterns, Authentication Methods, & Networks

3. Patterns for Databases, Websites, and Testing

4. Testing, Concurrency, and Performance Trends

I hope that this Low-Level Design Interview Questions & Answers has prepared you well for your next low level design interview.

All the Best!!!