System.ValueTuple by: Microsoft

Provides the System.ValueTuple structs, which implement the underlying types for C# 7 tuples. Commonly Used Types: System.ValueTuple System.ValueTuple<T1> System.ValueTuple<T1, T2> System.ValueTuple<T1, T2, T3> System.ValueTuple<T1, T2, T3, T4> System.ValueTuple<T1, T2, T3, T4, T5> System.ValueTuple<T1, T2, T3, T4, T5, T6> System.ValueTuple<T1, T2, T3, T4, T5, T6, T7> System.ValueTuple<T1, T2, T3, T4, T5, T6, T7, TRest> When using NuGet 3.x this package requires at least version 3.4.

System.Threading.Thread by: Microsoft

Provides the System.Threading.Thread class, which allows developers to create and control a thread, set its priority, and get its state.

System.Threading.Timer by: Microsoft

Provides the System.Threading.Timer class, which is a mechanism for executing a method at specified intervals. Commonly Used Types: System.Threading.Timer System.Threading.TimerCallback