C Academy · Lesson

Strings in C

Discover how strings are implemented in C using character arrays and how to manipulate them using built-in functions like strlen, strcpy, strcat, and strcmp.

Lesson 3 of 310 steps

Strings in C is a free C Academy lesson on CoddyKit. This is lesson 3 of 3. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the C Academy learning path, and your progress syncs across the web and the CoddyKit app. The C Academy course includes 3 lessons in total.

What Is a String in C?

Strings in C

In C, strings are sequences of characters stored in character arrays and terminated by a null character \0.

In this lesson, you will learn:

  • How to declare and initialize strings.
  • How to manipulate strings using standard functions.
  • The difference between character arrays and string literals.
Strings in C — illustration 1

Declaring a String

A string in C is declared as a character array.

Example:

char name[10];

This creates an array that can store a string of up to 9 characters plus the null terminator \0.

Initializing a String

Strings can be initialized in two ways:

  • Using a character array:
  • char name[] = {'J', 'o', 'h', 'n', '\0'};
  • Using a string literal:
  • char name[] = "John";

Printing a String

The printf function is used to print a string:

printf("%s", name);

Example:

char name[] = "Alice"; printf("Hello, %s!", name);

Example: Printing a String

This program demonstrates how to store and print a string.

#include <stdio.h>

int main() {
    char name[] = "Alice";
    printf("Hello, %s!\n", name);
    return 0;
}

String Input Using scanf()

To read a string input from the user, use scanf:

char name[20]; scanf("%s", name);

Warning: scanf does not read spaces in strings.

Example: Taking String Input

This program demonstrates how to take a string input using scanf.

#include <stdio.h>

int main() {
    char name[20];
    printf("Enter your name: ");
    scanf("%s", name);
    printf("Hello, %s!\n", name);
    return 0;
}

Common String Functions

C provides several string manipulation functions:

  • strlen(str) - Returns string length.
  • strcpy(dest, src) - Copies one string to another.
  • strcat(dest, src) - Concatenates two strings.
  • strcmp(str1, str2) - Compares two strings.

String Basics Recap

Summary

In this lesson, you learned:

  • How to declare and initialize strings.
  • How to print and take string input.
  • How to use basic string functions.

Next, we will explore pointers and memory management in C!

Strings in C — illustration 10
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Frequently Asked Questions

Is the “Strings in C” lesson free?

Yes — the full text of “Strings in C” is free to read here on the web. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the C Academy course, upgrade to CoddyKit PRO. The C Academy course includes 3 lessons in total.

What will I learn in “Strings in C”?

Discover how strings are implemented in C using character arrays and how to manipulate them using built-in functions like strlen, strcpy, strcat, and strcmp. You practise C Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start C Academy?

No prior experience is required. C Academy on CoddyKit is structured for beginners through advanced learners, so you can start here or from the beginning and move at your own pace. This is lesson 3 of 3.

How long does the “Strings in C” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this C Academy lesson?

Yes. Every C Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

All lessons in this course

  1. Introduction to Arrays
  2. Multidimensional Arrays
  3. Strings in C
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