Collections and Generics

There is scarcely even a code sample that doesn’t use a collection such as a List or a Dictionary . Large applications may have hundreds of thousands of collection instances in concurrent use. Selecting the right collection type for your needs — or trying to do better by writing your own — can provide significant performance benefits to many applications. Because as of .NET 2.0, collections are intimately linked with the CLR implementation of generic types, we begin our discussion with generics.