Data structures

Linked lists, arrays, hash tables, etc. – a data structure is a representation of data that makes desired operations efficient, often at the cost of making other operations inefficient.

It is sometimes useful to distinguish concrete data structures, the actual representation of the data and the definition of the algorithms, from abstract data types, the abstract behavior that the concrete structures implement. Sequences and maps are abstract data types; linked lists and hash tables are concrete data structures.

Data structures are a core part of an undergraduate computer science education, though just as I've never had to care about quicksort and merge sort since my college days, I've gotten pretty far in my career with just arrays and hash tables…

Posts

• "Notes on tree data structures" (Sep 2025)