namespace Linq

in global :: System

This namespace contains:

class Enumerable Provides a set of ( in Visual Basic) methods for querying objects that implement .
interface IGrouping<TKey,TElement> Represents a collection of objects that have a common key.
interface ILookup<TKey,TElement> Defines an indexer, size property, and Boolean search method for data structures that map keys to sequences of values.
interface IOrderedEnumerable<TElement> Represents a sorted sequence.
class Lookup<TKey,TElement> Represents a collection of keys each mapped to one or more values.