System.Diagnostics.Debug by: Microsoft

Provides classes and attributes that allows basic interaction with a debugger. Commonly Used Types: System.Diagnostics.Debug System.Diagnostics.DebuggerStepThroughAttribute System.Diagnostics.Debugger System.Diagnostics.DebuggerDisplayAttribute System.Diagnostics.DebuggerBrowsableAttribute System.Diagnostics.DebuggerBrowsableState System.Diagnostics.DebuggerHiddenAttribute System.Diagnostics.DebuggerNonUserCodeAttribute System.Diagnostics.DebuggerTypeProxyAttribute

System.Diagnostics.DiagnosticSource by: Microsoft

Provides Classes that allow you to decouple code logging rich (unserializable) diagnostics/telemetry (e.g. framework) from code that consumes it (e.g. tools) Commonly Used Types: System.Diagnostics.DiagnosticListener System.Diagnostics.DiagnosticSource

System.Diagnostics.TextWriterTraceListener by: Microsoft

Provides trace listeners for directing tracing output to a text writer, such as System.IO.StreamWriter, or a stream, such as a System.IO.FileStream. Commonly Used Types: System.Diagnostics.TextWriterTraceListener System.Diagnostics.DelimitedListTraceListener

System.Diagnostics.Tools by: Microsoft

Provides attributes, such as GeneratedCodeAttribute and SuppresMessageAttribute, that are emitted or consumed by analysis tools. Commonly Used Types: System.CodeDom.Compiler.GeneratedCodeAttribute System.Diagnostics.CodeAnalysis.SuppressMessageAttribute

System.Diagnostics.TraceSource by: Microsoft

Provides classes that help you trace the execution of your code. Developers should prefer the classes in the ETW-based System.Diagnostics.Tracing package. Commonly Used Types: System.Diagnostics.TraceListener System.Diagnostics.TraceLevel System.Diagnostics.TraceSource System.Diagnostics.TraceEventType System.Diagnostics.DefaultTraceListener System.Diagnostics.Trace

System.Drawing.Primitives by: Microsoft

Provides basic drawing primitive structures, that exposes the corresponding System.Drawing.dll types in .NET Core. Commonly Used Types: System.Drawing.Point System.Drawing.PointF System.Drawing.Size System.Drawing.SizeF System.Drawing.Rectangle System.Drawing.RectangleF When using NuGet 3.x this package requires at least version 3.4.

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.IdentityModel.Tokens.Jwt by: >Microsoft Open Technologies Inc.

This package provides an assembly containing classes which extend the .NET Framework 4.5 with the necessary logic to process the JSON Web Token (JWT) format. That includes validating, parsing and generating JWT tokens; those capabilities can be applied both within the Windows Identity Foundation token processing pipeline and standalone, without any dependency on WIF’s configuration.

System.Interactive.Async by: .NET Foundation and Contributors

Interactive Extensions Async Library used to express queries over asynchronous enumerable sequences.

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.Abstractions by: Tatham Oddie

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

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.IO.FileSystem.DriveInfo by: Microsoft

Provides the System.IO.DriveInfo class, which enables developers to query local drive information. Commonly Used Types: System.IO.DriveInfo System.IO.DriveType System.IO.DriveNotFoundException

System.IO.Pipelines by: Microsoft Corporation

An abstraction for doing efficient asynchronous IO

System.Json by: Microsoft

Provides standards-based support for the serialization of JavaScript Object Notation (JSON). Commonly Used Types: System.Json.JsonArray System.Json.JsonObject System.Json.JsonPrimitive System.Json.JsonValue When using NuGet 3.x this package requires at least version 3.4.

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.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.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.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