juniorStrings

What is a String and how is it stored in memory?

Updated Apr 28, 2026

Short answer

A string is a sequence of characters, typically stored as a contiguous array of bytes or integers (Unicode).

Deep explanation

Strings are one of the most common data types. A string is a sequence of characters, typically stored as a contiguous array of bytes or integers (Unicode). Understanding how they are represented (ASCII/UTF-8/UTF-16) is key to solving character encoding issues.

Real-world example

Storing user names or IDs in an application.

Common mistakes

  • Modifying a string inside a long loop without using a StringBuilder/StringBuffer.

Follow-up questions

  • What is the time complexity of concatenation?

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