Interview Q&A / System Design
System Design interview questions
Caching, scaling, databases and classic design problems for beginners.
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- What is the CAP theorem, in simple words?
The CAP theorem says that when a network partition splits a distributed system, it must choose between consistency (every read sees the latest write or gets an error) and availability (every request gets a non-error response, possibly stale). Partitions can't be ruled out, so the real choice is CP or AP during a partition.
IntermediateIn-depth4 min read - What is the difference between strong and eventual consistency?
Strong consistency means every read sees the latest completed write. Eventual consistency means replicas may briefly return old data but will all converge to the same value if no new writes arrive.
BeginnerQuick answer1 min read