What Is a Linked List? Explained Simply

What a linked list is

A linked list is a data structure that stores a sequence of items, where each item points to the next one, forming a chain. Each element, called a 'node,' holds two things: the data itself and a reference (a link) to the following node. Starting from the first node, you can follow the links from one to the next until you reach the end. This chain-of-links design gives the linked list very different characteristics from an array.

How it differs from an array

An array stores its elements in one contiguous block of memory, numbered by position, so you can jump instantly to any element. A linked list scatters its nodes, connecting them with links instead. This means you cannot jump directly to the fifth item; you have to follow the chain from the start. In exchange, a linked list makes it easy to insert or remove items anywhere, something arrays handle awkwardly. The two structures trade off in opposite ways.

Easy insertion and removal

The linked list's biggest strength is flexibility. To insert a new item, you simply adjust a couple of links to splice the new node into the chain, no need to shift other elements around. Removing an item is just as easy: you reroute the links to skip over it. In an array, inserting or removing in the middle can require moving many elements. For data that changes size and shape often, a linked list can be more efficient.

The trade-offs

Linked lists are not always the better choice. Because you must follow links from the beginning to reach a specific position, accessing an element by its index is slower than with an array. Linked lists also use a little extra memory to store the links, and their scattered nodes can be less friendly to how modern processors cache data. Choosing between an array and a linked list means matching the structure's strengths to what your program does most.

Variations and uses

Linked lists come in variations: a 'singly' linked list points only forward, while a 'doubly' linked list has links in both directions, letting you move backward too. Linked lists are used to build other data structures like stacks and queues, and appear in many programs that need flexible, frequently-changing sequences. While some modern languages favor arrays and dynamic arrays for everyday use, linked lists remain an important concept and tool in programming.

Why it matters

The linked list is a classic data structure that teaches a fundamental lesson: different structures suit different needs. Understanding how linked lists trade instant access for easy insertion and removal, compared to arrays, builds the kind of thinking that helps programmers choose the right tool for each job. It is a staple of computer science education and a concept that deepens your understanding of how data can be organized in memory.

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See also: What is an array? Explained simply, What is Big O notation? Explained.

Sources

• Linked list - Wikipedia

Published date reflects the original event date (2024-10-08). This article is original Skillo editorial written from the sources above; facts were verified in September 2026.