A data structure is an algebraic structure about data. It is a collection of data values, their relationships, and the functions or operations that can remain applied to the data. A data structure in computer science is a data organisation, management, and storage format typically chosen for efficient data access.

Data structures are the foundation for abstract data types (ADT). The data structure implements the physical condition of the data type. The ADT specifies the data type logical form.

Different data structures remain better suited to varying types of applications, and some are highly specialised to specific tasks. Relational databases, for example, frequently use B-tree indexes for data retrieval. While hash tables remain commonly used in compiler implementations to look up identifiers.

Data structures enable the efficient management of large amounts of data for applications such as large databases and internet indexing services. In most cases, efficient data structures are essential for designing efficient algorithms. Some formal design methods and programming languages emphasise data structures as the primary organising factor in software design rather than algorithms. Data structures can be used to organise the storage and retrieval of information from primary and secondary memory.