#123 What is a Hash Table?

#123 What is a Hash Table?

Author: David Kopec, Rebecca Kopec September 4, 2023 Duration: 19:58

Hash tables are some of the most widely used and powerful data structures. They allow for the efficient storage of key-value pairs. Keys are identifiers that we want to lookup data by, while values are the actual data. Hash tables underly common abstract data types in programming languages used for key-value data known as dictionaries, maps, or associative arrays. Hash tables can accomplish lookups, insertions, updates, and deletions in constant time on average. In this episode we explain what hash tables are used for and how they work.

If you don't know what an array or linked list is, you probably first want to listen to our prior episode, "What is a Data Structure?" Arrays and linked lists are component parts of hash tables and referred to in the episode with assumed knowledge about them.

Show Notes

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Read transcript



Ever wondered how the apps on your phone actually work, or what really happens when you click "download"? Kopec Explains Software is here to demystify those everyday digital mysteries. Hosted by David and Rebecca Kopec, this conversation breaks down complex, software-related ideas into clear, relatable concepts you can grasp. The focus isn't on jargon or textbook definitions, but on building a genuine, intuitive feel for how technology operates. Each episode picks apart a different facet of the software world, from the fundamentals of coding to the ethics of artificial intelligence, translating technical subjects into plain English. You'll come away not just with new knowledge, but with a clearer framework for understanding the digital systems that shape our lives. It’s a straightforward, engaging resource for anyone with curiosity about the technology they use daily, whether you're a seasoned professional looking for a fresh perspective or a complete novice starting from scratch. Tune into the podcast for thoughtful discussions that make the vast and often intimidating landscape of software feel accessible and genuinely interesting.
Author: Language: en-us Episodes: 100

Kopec Explains Software
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