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Programming Concepts Intermediate

What is Hash Table?

A data structure that maps keys to values using a hash function, providing average O(1) time complexity for lookups, insertions, and deletions.

Hash tables compute a hash of the key to determine where to store the value in an array. Collisions (different keys mapping to same index) are handled by chaining (linked lists) or open addressing (probing nearby slots).

Hash tables power dictionaries (Python dict), objects (JavaScript), HashMaps (Java), and associative arrays (PHP). They are the most commonly used data structure for fast key-based lookups. Performance degrades with many collisions or high load factors.

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Concurrency
The ability of a program to manage multiple tasks that can make progress during overlapping time periods.
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The practice of designing application programming interfaces that are consistent, intuitive, and maintainable for developers to consume.
Data Structure
A way of organizing and storing data in a computer so it can be accessed and modified efficiently.
Event-Driven Architecture
A software design pattern where components communicate by producing and consuming events rather than direct method calls.
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