# What is DSA? — Data Structures & Algorithms

Source: https://www.geekswithgeeks.com/en/dsa/dsa-intro

> A data structure organises data; an algorithm is a recipe that operates on it.

## Two halves of one skill

A **data structure** decides *how data is stored and connected* (array, list, tree, graph). An **algorithm** is a *finite sequence of steps* that transforms input into a desired output. Good code picks the structure that makes the algorithm cheap.

## Kitchen analogy

The data structure is how you arrange your pantry — labelled jars vs. one big box. The algorithm is the recipe. The same recipe is fast with a tidy pantry and slow when you dig through the box each time.

## Why interviews test it

DSA questions reveal whether you can spot the underlying pattern, reason about cost, and handle edge cases — skills that transfer to real system work far more than trivia does.

## How to use this course

For each topic: understand the picture first, then the operations, then the code. If you can redraw the diagram from memory, you understand it.