Suggest an editImprove this articleRefine the answer for “What is a linked list?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)A **linked list** is a data structure in which elements (called **nodes**) are stored **not sequentially in memory**, but **connected to each other by references (pointers)**. **Key point:** a linked list is a dynamic structure where elements are connected by references rather than laid out sequentially; it is flexible but slower than an array for random access.Shown above the full answer for quick recall.Answer (EN)ImageA **linked list** is a data structure in which elements (called **nodes**) are stored **not sequentially in memory**, but **connected to each other by references (pointers)**. Each node knows **where the next element is located**, and sometimes the previous one too. --- ### **1. Node structure** A single node usually contains: - **data (value)** - the value itself, - **a reference (next)** - the address of the next node. ```javascript [data | reference to the next] ``` Example (singly linked list): ```javascript head → [10 | *] → [20 | *] → [30 | None] ``` --- ### **2. Types of linked lists** | Type | Features | |---|---| | **Singly linked** | Each node stores a reference only to the next element. Movement is forward only. | | **Doubly linked** | Each node stores references to the **previous** and **next**. You can move in both directions. | | **Circular** | The last node (`tail`) points to the first (`head`), forming a ring. | --- ### **3. Basic operations** | Operation | Complexity | Comment | |---|---|---| | Access by index | **O(n)** | You need to walk through all nodes up to the target one. | | Insertion/deletion (given a known node) | **O(1)** | Only references are changed. | | Searching for an element | **O(n)** | Sequential traversal. | --- ### **4. Difference from an array** | Criterion | Array | Linked list | |---|---|---| | Storage | Contiguous in memory | Scattered, connected by references | | Access by index | O(1) | O(n) | | Insertion/deletion | Slow (O(n)) | Fast (O(1)) | | Size | Usually fixed | Can change dynamically | --- ### **5. Use cases** Linked lists are used when: - **frequent adding and removing** of elements is required; - the data size is **unknown** in advance; - memory can be **fragmented** (for example, in systems programming). --- **Summary:** > A **linked list** is a dynamic structure where elements are connected by references rather than laid out sequentially. > It is flexible, but slower than an array for random access.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.