Beginner~3h
Fundamentals in System DesignInterview Readiness Check
Core concepts: client-server model, HTTP, APIs, and system components.
httpapiclient-serverprotocolsbasicsfundamentals
Learning path
Try a sample question
What is latency in a distributed system?
A.The number of requests a system can handle per second
B.The percentage of time a system is operational
C.The time taken for a single request to travel from sender to receiver and get a response
D.The amount of data transferred per second
Sign up free to take the full check and see the answer with an explanation.
What this module tests
- Conceptual understanding of fundamentals fundamentals
- Trade-offs and design decisions in real system scenarios
- http and api — applied knowledge
- Interview-style reasoning and explanation quality
Free to start
Take the Fundamentals check →
10 questions · Dimension scoring · AI coach feedback · Shareable result
Test your knowledge — free →No credit card · Takes 10–15 min
Frequently asked questions
- What does the Fundamentals check test?
- The check covers core concepts: client-server model, http, apis, and system components. Questions span beginner to advanced difficulty and test both conceptual understanding and practical trade-off reasoning.
- What keywords should I know for Fundamentals?
- Key concepts include: http, api, client-server, protocols, basics, fundamentals. These frequently appear in system design interviews at product and infrastructure companies.
- How many questions are in the check?
- Each check has 10 questions — a mix of MCQ and short-answer. You get scored by dimension (e.g., scalability, consistency) so you know exactly where to focus.
- How long does it take to study Fundamentals?
- Most engineers spend around 3 hours on this module. The check itself takes about 10–15 minutes. You can retake it up to 3 times per day.
- What prerequisite knowledge do I need before Fundamentals?
- Fundamentals is a foundational module — no prerequisites needed.
- Is http, api, client-server covered?
- Yes. The Fundamentals module covers http, api, client-server among other key concepts. The check includes questions that reflect real system design interview patterns.
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