> For the complete documentation index, see [llms.txt](https://catherine-leung.gitbook.io/data-strutures-and-algorithms/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://catherine-leung.gitbook.io/data-strutures-and-algorithms/lists.md). # Lists A list is an **sequence of values**. It may have properties such as being sorted/unsorted, having duplicate values or being unique. The most important part about list structures is that the data has an ordering (which is not the same as being sorted). Ordering simply means that there is an idea that there is a "first" item, a "second" item and so on. Lists typically have a subset of the following operations: * initialize * add an item to the list * remove an item from the list * search * sort * iterate through all items * and more... A list may implement only a subset of the above functionality. The description of a list is very general and it can be implemented in a number of different ways. Two general implementation methods are the array method or the linked list method. We will look at each in turn. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://catherine-leung.gitbook.io/data-strutures-and-algorithms/lists.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.