System.Memory by: Microsoft

Provides types for efficient low-allocation access to memory. Commonly Used Types: System.Span af7d2ae49c79bb279625de4e92f7f91f9fe94f5d When using NuGet 3.x this package requires at least version 3.4.

System.IO.FileSystem.Primitives by: Microsoft

Provides common enumerations and exceptions for path-based I/O libraries. Commonly Used Types: System.IO.DirectoryNotFoundException System.IO.FileAccess System.IO.FileLoadException System.IO.PathTooLongException System.IO.FileMode System.IO.FileShare System.IO.FileAttributes

System.IO.FileSystem by: Microsoft

Provides types that allow reading and writing to files and types that provide basic file and directory support. Commonly Used Types: System.IO.FileStream System.IO.FileInfo System.IO.DirectoryInfo System.IO.FileSystemInfo System.IO.File System.IO.Directory System.IO.SearchOption System.IO.FileOptions

System.Globalization by: Microsoft

Provides classes that define culture-related information, including language, country/region, calendars in use, format patterns for dates, currency, and numbers, and sort order for strings. Commonly Used Types: System.Globalization.DateTimeFormatInfo System.Globalization.CultureInfo System.Globalization.NumberFormatInfo System.Globalization.CalendarWeekRule System.Globalization.TextInfo System.Globalization.Calendar System.Globalization.CompareInfo System.Globalization.CompareOptions System.Globalization.UnicodeCategory

System.IO.Compression by: Microsoft

Provides classes that support the compression and decompression of streams. Commonly Used Types: System.IO.Compression.DeflateStream System.IO.Compression.GZipStream System.IO.Compression.CompressionMode System.IO.Compression.CompressionLevel System.IO.Compression.ZipArchiveEntry System.IO.Compression.ZipArchive System.IO.Compression.ZipArchiveMode

System.IO.Compression.ZipFile by: Microsoft

Provides classes that support the compression and decompression of streams using file system paths. Commonly Used Types: System.IO.Compression.ZipFile

System.Linq.Queryable by: Microsoft

Provides classes for querying data structures that implement IQueryable<T>. Commonly Used Types: System.Linq.Queryable System.Linq.EnumerableQuery<T> System.Linq.EnumerableQuery

System.Globalization.Extensions by: Microsoft

Provides classes for performing unicode string normalization, culture-specific string comparisons and support the use of non-ASCII characters for Internet domain names. Commonly Used Types: System.StringNormalizationExtensions System.Text.NormalizationForm System.Globalization.IdnMapping

System.IO by: Microsoft

Provides base input and output (I/O) types, including System.IO.Stream, System.IO.StreamReader and System.IO.StreamWriter, that allow reading and writing to data streams Commonly Used Types: System.IO.Stream System.IO.IOException System.IO.EndOfStreamException System.IO.FileNotFoundException System.IO.MemoryStream System.IO.StreamReader System.IO.StreamWriter System.IO.StringWriter System.IO.TextWriter System.IO.TextReader

System.IO.FileSystem.Watcher by: Microsoft

Provides the System.IO.FileSystemWather class, which listens to the file system change notifications and raises events when a directory, or a file in a directory, changes. Commonly Used Types: System.IO.FileSystemWatcher System.IO.WatcherChangeTypes System.IO.FileSystemEventArgs System.IO.RenamedEventArgs System.IO.FileSystemEventHandler System.IO.RenamedEventHandler System.IO.NotifyFilters System.IO.ErrorEventArgs System.IO.ErrorEventHandler System.IO.WaitForChangedResult

System.Linq.Expressions by: Microsoft

Provides classes, interfaces and enumerations that enable language-level code expressions to be represented as objects in the form of expression trees. Commonly Used Types: System.Linq.Expressions.Expression<TDelegate> System.Linq.Expressions.Expression System.Linq.Expressions.MemberExpression System.Linq.Expressions.ExpressionVisitor System.Linq.Expressions.MethodCallExpression System.Linq.IQueryable<T> System.Linq.IQueryable System.Linq.Expressions.NewExpression System.Linq.Expressions.ParameterExpression System.Linq.Expressions.ConstantExpression

System.Net.NameResolution by: Microsoft

Provides the System.Net.Dns class, which enables developers to perform simple domain name resolution. Commonly Used Types: System.Net.Dns System.Net.IPHostEntry

System.Globalization.Calendars by: Microsoft

Provides classes for performing date calculations using specific calendars, including the Gregorian, Julian, Hijri and Korean calendars. Commonly Used Types: System.Globalization.HijriCalendar System.Globalization.GregorianCalendar System.Globalization.HebrewCalendar System.Globalization.KoreanCalendar System.Globalization.ThaiBuddhistCalendar System.Globalization.TaiwanCalendar System.Globalization.JapaneseCalendar System.Globalization.GregorianCalendarTypes System.Globalization.PersianCalendar System.Globalization.UmAlQuraCalendar

System.Linq by: Microsoft

Provides classes and interfaces that supports queries that use Language-Integrated Query (LINQ). Commonly Used Types: System.Linq.Enumerable System.Linq.IGrouping<TKey, TElement> System.Linq.IOrderedEnumerable<TElement> System.Linq.ILookup<TKey, TElement> System.Linq.Lookup<TKey, TElement>

System.Net.Http.WinHttpHandler by: Microsoft

Provides access to a high performance HTTP client handler based on the native Windows HTTP Services (WinHTTP) API. Commonly Used Types: System.Net.Http.WinHttpHandler

System.IO.Pipes by: Microsoft

Provides a means for interprocess communication through anonymous and/or named pipes. Commonly Used Types: System.IO.Pipes.NamedPipeServerStream System.IO.Pipes.PipeDirection System.IO.Pipes.PipeOptions System.IO.Pipes.PipeTransmissionMode System.IO.Pipes.NamedPipeClientStream System.IO.Pipes.PipeStream

System.IO.Abstractions by: Tatham Oddie

Just like System.Web.Abstractions, but for System.IO. Yay for testable IO access!

System.Linq.Parallel by: Microsoft

Provides classes that supports parallel queries that use Language-Integrated Query (LINQ). Commonly Used Types: System.Linq.ParallelQuery<TSource> System.Linq.ParallelEnumerable System.Linq.ParallelQuery System.Linq.OrderedParallelQuery<TSource>

System.IO.MemoryMappedFiles by: Microsoft

Provides classes for using a memory-mapped file, which maps the contents of a file to an application's logical address space. Commonly Used Types: System.IO.MemoryMappedFiles.MemoryMappedViewAccessor System.IO.MemoryMappedFiles.MemoryMappedViewStream System.IO.MemoryMappedFiles.MemoryMappedFile System.IO.MemoryMappedFiles.MemoryMappedFileAccess

System.Net.NetworkInformation by: Microsoft

Provides access to network traffic data, network address information, and notification of address changes for the local computer. Commonly Used Types: System.Net.NetworkInformation.NetworkInterface System.Net.NetworkInformation.NetworkInformationException System.Net.NetworkInformation.NetworkAddressChangedEventHandler System.Net.NetworkInformation.NetworkInterfaceType System.Net.NetworkInformation.OperationalStatus System.Net.NetworkInformation.IPGlobalProperties System.Net.NetworkInformation.UnicastIPAddressInformation System.Net.NetworkInformation.UnicastIPAddressInformationCollection System.Net.NetworkInformation.PhysicalAddress System.Net.NetworkInformation.TcpConnectionInformation