C# Programming/Keywords/volatile

The volatile keyword is used to declare a variable that may change its value over time due to modification by an outside process, the system hardware, or another concurrently running thread.

You should use this modifier in your member variable declaration to ensure that whenever the value is read, you are always getting the most recent (up-to-date) value of the variable.

class MyClass
  public volatile long systemclock;

C# Keywords
abstract as base bool break
byte case catch char checked
class const continue decimal default
delegate do double else enum
event explicit extern false finally
fixed float for foreach goto
if implicit in int interface
internal is lock long namespace
new null object operator out
override params private protected public
readonly ref return sbyte sealed
short sizeof stackalloc static string
struct switch this throw true
try typeof uint ulong unchecked
unsafe ushort using var virtual
void volatile while
Special C# Identifiers (Contextual Keywords)
add alias async await dynamic
get global nameof partial remove
set value when where yield
Contextual Keywords (Used in Queries)
ascending by descending equals from
group in into join let
on orderby select where

This keyword has been part of the C# programming language since .NET Framework 1.1 (Visual Studio 2003).