Discover Data Structures in JavaScript with step-by-step visualizations and interactive exercises. Gain insights into arrays, stacks, queues, dictionaries, sets, hash tables, linked lists, binary trees, and graphs.

This course provides a quick introduction to Data Structures using JavaScript. The audience for this course is someone who understands the basics of programming in JavaScript (e.g. an undergrad student or a coding boot camp graduate). Data Structures included in this course are Array, Stack, Queue, Dictionary, Set, Hash Table, Linked List, Binary Tree, and Binary Search Tree and Graphs. Each tutorial includes step-by-step visualizations and interactive exercises.

Data Structures in JavaScript: Visualizations & Exercises

A Hash table is a data structure that is used to implement an associative array of a key and value. How is it different from a dictionary?

A dictionary is a 1:1 map of a key/value pair. Hashtable is a more efficient way of storing key/value pairs. It is designed around an array where each array cell is called a _**bucket**_. Each bucket contains a list of key/value pairs. When a key/value pair is inserted into a hashtable, we first compute its destination bucket. We determine the bucket by applying a special function on the key. This special function is known as the _**hash function**_. Every hash function returns a number based on the key. This number is the bucket Id. We then go to the bucket and append this key/value pair to the list of key/value pairs in the bucket.

Here's a quick visualization to look at the hash table (Our Hash Table has 5 buckets).

Data Structures in JavaScript Exam

Hash Table