Hack provides several built-in data structures that you can utilize for organizing and manipulating data efficiently. Here are some of the different types of data structures available in Hack:

1.  Arrays : Arrays are indexed collections of elements. In Hack, arrays can be indexed by integers or strings. They can store multiple values of the same or different types. Arrays can be numerically indexed or associative, where keys are strings instead of integers.

2.  Vectors : Vectors, also known as dynamic arrays, are similar to arrays but can dynamically resize themselves as elements are added or removed. Vectors provide efficient random access to elements and are commonly used when the size of the collection is not known in advance.

3.  Sets : Sets are unordered collections that store unique elements. Hack provides two types of sets: `Set<T>`, which stores elements of a specific type, and `Keyset<T>`, which stores unique keys of a map. Sets are useful for membership testing and eliminating duplicate entries.

4.  Maps : Maps, also called dictionaries or associative arrays, store key-value pairs. Hack provides two types of maps: `Map<K, V>`, where keys and values can be of any type, and `Dict<K, V>`, where keys must be of a specific type. Maps are useful for efficient lookup and retrieval of values based on keys. 5.  Tuples : Tuples are fixed-size collections that can hold a fixed number of elements of different types. They provide a convenient way to group multiple values together.

6. Collections : Hack's standard library includes additional data structures such as `Deque<T>` (double-ended queue), `Pair<T1, T2>` (a pair of values), and `VectorMap<K, V>` (a combination of a vector and a map), among others.

Apart from these built-in data structures, you can also define and use custom data structures in Hack by creating classes or structures that encapsulate the desired functionality and organization of data.

Each data structure has its own characteristics, advantages, and use cases. The choice of data structure depends on the specific requirements of your program, such as the type of data to be stored, the expected operations, and the efficiency considerations for various operations like insertion, deletion, retrieval, and iteration.