What Is a String in Programming?

What a string is

In programming, a string is a data type that represents text, a sequence of characters such as letters, digits, spaces, and symbols. A string can be a single character, a word, a sentence, or an entire document. The name comes from the idea of characters 'strung' together in order. Strings are one of the most common and important data types, because so much of what programs handle, names, messages, addresses, and all kinds of text, is stored as strings.

How strings are written

In code, strings are usually written inside quotation marks, which tell the computer where the text begins and ends. For example, a greeting might be written as 'Hello, world!' in quotes. The quotes are not part of the text itself; they just mark it as a string. This simple convention lets programs include text of any kind, and it distinguishes a piece of text from, say, a variable name or a number, which are written without quotes.

Characters in order

A string is essentially an ordered sequence of individual characters, and that order matters. Because the characters have positions, you can access individual ones, pick out a portion of the text, or go through them one at a time. This ordered nature means strings share some behavior with other ordered collections: you can measure their length, examine specific positions, and loop through them, which makes many text-processing tasks possible.

Common string operations

Programs do many things with strings. 'Concatenation' joins two strings into one, useful for building messages from pieces. You can search a string for a word, replace parts of it, change its case, trim extra spaces, or split it into pieces. You can also check its length or compare two strings. These operations are the everyday tools of text handling, and most programming languages provide a rich set of them built in, because working with text is so common.

Text is everywhere

Strings are essential because text is everywhere in software. User names, passwords, search queries, messages, file names, web addresses, and the content of this very article are all strings. Any time a program accepts input you type, displays words on screen, or stores information as text, it is working with strings. This ubiquity makes strings one of the most frequently used data types, and handling them well is a core programming skill.

Why it matters

Strings are a fundamental data type that every programmer uses constantly, because handling text is central to almost all software. Understanding what strings are, how they store characters in order, and the common operations you can perform on them gives you the tools to work with words and text in code. For anyone learning to program, strings are an essential concept, right alongside numbers, that you will rely on in nearly every project.

Related on Skillo

See also: What is a data type? Explained simply, What is a variable in programming?.

Sources

• String (computer science) - Wikipedia

Published date reflects the original event date (2024-06-25). This article is original Skillo editorial written from the sources above; facts were verified in September 2026.