.NET has many data structures which implement collections, sets, queues and other types of common data structures. Knowing which classes to use for your needs is critical to building great applications. This presentation will examine common data structures such as List, Dictionary, HashSet, LinkedList, SortedList, SortedSet, SortedDictionary, Queue, PriorityQueue, ConcurrentQueue, ConcurrentDictionary, ImmutableList, ImmutableDictionary. We will discuss implementation details such as capacity, memory, CPU, performance, and concurrency. By the end of this presentation, you will have a good understanding of when to use each data structure along with some best practices for using them.