Start here · No DSA experience needed

What is DSA?

DSA stands for Data Structures and Algorithms. It is the art of organizing information and solving problems step by step — so your programs can work correctly and efficiently.

Think of finding a book in a library. How books are arranged is the data structure; how you find a book is the algorithm.

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Plain English explanations · Hands-on examples · Python and Java routes

Lesson 01 — Foundations

Understand the two halves of DSA

You already use DSA ideas every day. A phone's contact list, a shopping cart, and map directions all depend on how data is stored and how problems are solved.

01 · Data structures

Where information lives

A data structure is a way to store and organize data. Examples include arrays/lists, stacks, queues, dictionaries/maps, trees and graphs.

02 · Algorithms

What to do with information

An algorithm is a clear sequence of steps that solves a problem, such as searching, sorting, finding a route or calculating a result.

03 · Efficiency

How well a solution scales

Two algorithms can produce the same answer but take different amounts of time or memory. This is why we study time and space complexity.

A tiny hands-on demo

Find a number in an array

Below are five numbers. Choose a target and click Search. The algorithm checks numbers from left to right until it finds the target.

Try a linear search

8
3
12
5
9

Array indices start at 0, not 1.

Try searching for 12.

Equivalent Python code

numbers = [8, 3, 12, 5, 9]
target = 12

for i, value in enumerate(numbers):
    if value == target:
        print("Found at index", i)
        break
else:
    print("Not found")

In the worst case, this algorithm checks every element. For n items, linear search takes O(n) time.

Choose your next step

Pick a comfortable learning path

You do not need to learn every programming language. Start with the one you already know, or use Python if you're choosing your first.

Beginner favourite

Start with Python →

Learn basic programming, conditions, loops, lists and then sorting.

School & Java learners

Start with Java →

Build logic through Java fundamentals before moving into algorithm practice.

Visual and practical

Understand sorting →

Compare bubble, selection, insertion, merge and quick sort through lessons.

Not sure what to study?

Personalized learning plan →

Use our existing DSA Learning Path Finder to select a focused syllabus.

One week to get started

Your first seven days of DSA

A suggested plan, not a deadline. Repeat a day whenever you need more practice.

Day 1Understand DSA
Day 2Lists and arrays
Day 3Loops and tracing
Day 4Linear search
Day 5Sorting basics
Day 6Complexity O(n)
Day 7Three exercises
Keep exploring

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